A
ABS — Anti-lock Braking System
Braking and safety
Modulates brake pressure to help prevent wheel lock during braking, preserving steering control. ABS cannot create tire grip where none is available.
ACC — Adaptive Cruise Control
Braking and safety
Adjusts vehicle speed to help maintain a selected following gap. In wiring or ignition-switch descriptions, ACC can instead mean accessory power. Read the abbreviation in context.
Accumulator
Hydraulics
Stores hydraulic energy under pressure so the system can operate the clutch and gear actuators. It helps stabilize pressure and reduce pump cycling; it does not generate pressure itself.
Actuator (clutch / gear)
Clutch
A device that turns a control command into movement. A clutch actuator operates the clutch; a gear actuator moves the mechanism that selects or engages a gear.
Adaptive learning / self-learning
Electrical and diagnostics
Adjustments the transmission computer makes to learned operating values. Depending on the system, a diagnostic learning procedure may also be required after repair.
ADAS — Advanced Driver Assistance Systems
Braking and safety
A group of driver-support features such as collision warnings, adaptive cruise control and lane assistance. Equipment and capability vary by model; sensors may need calibration after relevant repairs.
AEB — Automatic Emergency Braking
Braking and safety
A driver-assistance function that can apply braking when it detects an imminent collision within its operating limits. It does not replace driver attention.
AFR — Air–Fuel Ratio
Engine and exhaust
The proportion of air mass to fuel mass used for combustion. Target ratios vary with fuel, engine and operating conditions; a gasoline reference value is not universal for every fuel blend.
AGM / EFB battery
Electrical and diagnostics
AGM means Absorbent Glass Mat; EFB means Enhanced Flooded Battery. Both are lead-acid battery technologies used in appropriate applications. Replacement type, rating and any registration procedure must match the vehicle.
Alternator / starter motor
Electrical and diagnostics
The alternator supplies electrical power and charges the battery while the engine runs. The starter turns the engine for starting. Integrated starter-generators combine functions in some vehicles.
AMT — Automated Manual Transmission
Systems
A manual-type gearbox whose clutch and gear changes are operated by actuators under computer control. Ferrari F1, Maserati Cambiocorsa and Lamborghini E-Gear are examples. An AMT is different from a dual-clutch transmission.
Anti-roll bar / sway bar
Steering and suspension
Links suspension movement across an axle to resist body roll. It differs from a strut brace and from the springs or dampers.
APP — Accelerator Pedal Position
Engine and exhaust
The pedal-position signal used by electronic engine control to interpret driver demand. It is not the same measurement as throttle-valve position.
ASM — Aston Martin automated manual
Systems
Aston Martin uses ASM for its automated manual transmission systems. Service literature uses Auto-Shift Manual; other model literature uses Automatic Shift Manual or Automated Sequential Manual. An ASM car has a manual-type gearbox with automated clutch and gear actuation. When a listing says ASM unit, check whether it covers the hydraulic power unit, actuator or another assembly.
ATF — Automatic Transmission Fluid
Fluids
A fluid category used in specified transmission or hydraulic applications. ATF is not one universal formulation. The precise approval and application must match the vehicle’s requirements.
Automatic transmission (torque converter type)
Systems
A transmission that can change ratios automatically and commonly uses a torque converter to connect the engine to the transmission. It differs from an automated manual and from a DCT. An automatic driving mode or paddle shifters alone do not identify the internal gearbox design.
AWD / 4WD / RWD
Systems
AWD means all-wheel drive, 4WD means four-wheel drive and RWD means rear-wheel drive. These describe driven-wheel arrangements. The transfer units, couplings, differentials and control systems vary by vehicle; the abbreviation alone does not determine fitment.
B
Backlash / preload
Measurements
Backlash is the clearance between mating gear teeth. Preload is a deliberately applied initial load, often in bearings. Both require assembly-specific measurement and adjustment.
Balancing — static / dynamic
Clutch
Checking and correcting uneven mass distribution in a rotating component or assembly. Dynamic balancing considers imbalance during rotation, including its distribution across planes. Balancing does not repair a cracked part or correct all causes of clutch vibration.
Banjo fitting / sealing washer
Hydraulics
A fluid connection using a hollow bolt through a ring-shaped fitting, usually sealed by washers at the joint. Reuse and tightening requirements depend on the specified hardware and procedure.
Bar / psi
Measurements
Units of pressure. One bar is approximately 14.5 psi. A pressure rating or diagnostic value must refer to the correct circuit and conditions; a sensor’s range is not automatically the system’s target operating pressure.
BCM — Body Control Module
Electrical and diagnostics
Controls or coordinates body electrical functions such as lighting and locks, depending on the vehicle. It is different from the engine or transmission controller.
Bearing / thrust bearing
Gearbox
A bearing supports motion and load between parts. A thrust bearing primarily handles axial load along a shaft. Bearings are selected by function, dimensions, clearance and application, not appearance alone.
Bellhousing
Gearbox
The housing connecting the engine and transmission around the clutch or drive connection.
Bench testing
Ordering and service
Testing a removed component with workshop equipment under specified conditions. It checks the functions covered by that test; installation checks and vehicle calibration may still be necessary.
Bench-tested versus vehicle-tested
Ordering and service
Bench testing evaluates a removed component under specified workshop conditions. Vehicle testing checks its operation within the installed system. One does not automatically replace the other or include installation, bleeding and learning procedures.
Bite point
Clutch
The point at which the clutch begins transmitting torque. See PIS for the related setting used on applicable Ferrari F1 and Maserati systems.
Bleeding
Hydraulics
Removing trapped air from a hydraulic circuit. Air can interfere with pressure and actuator movement. The correct procedure depends on the vehicle and system.
BMS — Battery Management System
Hybrid and electric
Monitors and manages battery operation, including relevant cell voltages, temperatures and charging limits. It is different from a BCM body-control module.
Boost pressure
Engine and exhaust
Intake pressure produced by forced induction. A pressure figure must state whether it is gauge pressure above atmospheric pressure or absolute pressure. Boost alone does not define engine horsepower or clutch torque demand.
Brake booster / servo
Braking and safety
Reduces the driver effort needed to apply the brakes. Designs include vacuum and powered assistance; a booster is different from the hydraulic master cylinder.
Brake caliper / rotor / pad
Braking and safety
The caliper applies the pads to the rotating brake disc, also called a rotor. Friction slows the wheel and converts motion into heat. These are separate service components.
Brake master cylinder
Braking and safety
Converts pedal or booster force into hydraulic pressure for the brake circuits. It is distinct from a clutch master cylinder.
C
Calibration / adaptation
Electrical and diagnostics
A prescribed procedure that establishes or learns operating positions and control values after installation or repair. Calibration cannot repair worn parts, leaks or electrical faults.
Camber / caster / toe
Steering and suspension
Wheel-alignment measurements. Camber is wheel tilt viewed from the front; caster describes steering-axis inclination viewed from the side; toe describes whether wheels point inward or outward viewed from above.
Cambiocorsa — Maserati
Systems
An Italian name combining cambio (gearbox or gear change) and corsa (racing). It identifies Maserati’s automated manual system on applicable models. The driver can request shifts without operating a clutch pedal; hydraulic actuators carry out the clutch and gear movements. A Cambiocorsa pump rebuild does not include the entire transmission.
CAN bus — Controller Area Network
Electrical and diagnostics
The vehicle's communication network, allowing control modules such as the engine and transmission computers to exchange information.
CAN node
Electrical and diagnostics
A control module or device communicating on a Controller Area Network. Manual-conversion work can involve configuration of several nodes; changing one component does not ensure every module is correctly configured.
Cat-back / axle-back exhaust
Engine and exhaust
Cat-back generally describes the exhaust downstream of the catalytic converters; axle-back generally describes a rear exhaust section. Exact included components vary by kit, so check the itemized listing.
Catalytic converter / high-flow catalyst
Engine and exhaust
An exhaust component that helps reduce pollutants. High-flow describes a performance-oriented design, not proof of emissions approval. Check the exact product and permitted application rather than assuming fitment means road legality.
Cavitation / aeration
Measurements
Cavitation involves vapor bubbles forming and collapsing when local liquid pressure falls sufficiently. Aeration is air mixed into fluid. Both can affect pump performance, but they have different mechanisms.
CCA / Ah — Cold Cranking Amps / Ampere-hours
Electrical and diagnostics
CCA describes starting-current performance under a specified cold test. Ah describes charge capacity under stated test conditions. They measure different battery characteristics.
CCP unit — Getrag clutch hydraulic control assembly
Clutch
Commonly called the Clutch Control Panel in repair terminology; technical literature also uses Clutch Carrier Plate. In the Getrag 7DCL750 context, this assembly carries hydraulic components that control clutch operation, including valves and pressure feedback. In plain language: it controls how the clutches apply and release so engine power can reach the gearbox. It is separate from the friction clutch pack and from the SAP. The exact components serviced or replaced depend on the approved repair scope.
Cell count — catalytic converter
Engine and exhaust
Usually a description of substrate cell density, such as cells per square inch. Cell density alone does not establish emissions conversion performance, certification or compatibility.
Check valve / non-return valve
Hydraulics
A valve designed to allow flow in one direction and restrict flow in the opposite direction. Leakage through it can affect pressure retention.
CHRA — Center Housing Rotating Assembly
Engine and exhaust
The central turbocharger assembly containing the rotating shaft/wheels and bearing housing components. Replacing or rebuilding a CHRA does not automatically replace all external housings or the boost-control actuator.
CKP / CMP — Crankshaft / Camshaft Position sensor
Engine and exhaust
CKP reports crankshaft rotation and position; CMP identifies camshaft position. The controller uses these signals for synchronization, injection and ignition.
Clutch basket / carrier
Clutch
The structure that holds and drives parts of a multi-plate clutch assembly. Wear or damage can affect clutch operation.
Clutch disc / friction lining
Clutch
The disc and friction material that transmit torque when clamped. Relining replaces the friction material on a suitable reusable disc; it does not by itself replace every part of the clutch assembly.
Clutch drag
Clutch
The clutch continues transmitting unwanted torque when commanded to release. Possible effects include difficult gear engagement or vehicle creep; the cause requires diagnosis.
Clutch hub / spline
Clutch
The clutch hub connects the friction disc to the gearbox shaft through matching splines. Correct tooth count, dimensions and condition are essential; a disc with the wrong spline cannot be selected by outside diameter alone.
Clutch judder / chatter
Clutch
An uneven vibration or repeated grabbing during clutch take-up. Possible contributors include friction surfaces, contamination, geometry, mounts or control calibration. It is a symptom, not a diagnosis of one failed component.
Clutch kiss point
Clutch
Another term for the onset of torque transfer during clutch engagement. Different control systems learn or specify this point differently; it is related to bite point, but procedures and values are not universal.
Clutch pack
Clutch
A group of friction plates and mating plates that work together as a clutch. A DCT contains two independently controlled clutch paths.
Clutch piston
Clutch
A hydraulic piston that applies or releases a clutch within the relevant transmission design. A piston kit is a component repair, not automatically a complete friction-clutch replacement.
Clutch slip
Clutch
A difference in speed across an engaged clutch. Controlled slip is normal during takeoff; excessive unintended slip creates heat and can indicate wear, inadequate clamping pressure or another fault.
Clutch wear percentage
Clutch
A diagnostic estimate derived from learned positions and software calculations on applicable systems. It is not a direct measurement of lining thickness and must be assessed with correct calibration, operating history and physical condition.
Coding / programming / calibration
Electrical and diagnostics
Coding configures supported settings; programming installs or changes software; calibration establishes applicable operating parameters. These terms are related but not interchangeable, and none repairs a physical leak or damaged gear.
Common rail / CRDI
Engine and exhaust
Common-Rail Direct Injection uses a shared high-pressure fuel rail supplying electronically controlled injectors. It is widely associated with diesel engines; the rail is separate from the pump and injectors.
Compression ratio / compression test
Engine and exhaust
Compression ratio compares cylinder volume with the piston at the bottom and top of its stroke. A compression test measures cranking pressure; the two are different quantities.
Core / core clutch
Ordering and service
The used component supplied for rebuilding or returned as part of an exchange arrangement. Rebuild suitability depends on inspection of its condition and completeness.
Core charge / core deposit
Ordering and service
A charge associated with an exchange component. Any credit or refund depends on the specific listing's return requirements and acceptance criteria; it is not automatically applicable to every rebuild service.
Crank power / wheel power
Measurements
Power measured or estimated at the engine differs from power measured at the driven wheels. Drivetrain losses and test methods affect the relationship. Do not treat wheel and crank figures as equivalent when selecting a clutch.
CV joint / CV boot
Steering and suspension
CV means Constant Velocity. A CV joint transmits drive while accommodating operating angles; its boot retains grease and excludes dirt. A boot replacement does not restore an already worn joint.
Cylinder leak-down test
Engine and exhaust
Applies controlled air pressure to a cylinder to evaluate sealing. Where air escapes can help distinguish leakage past valves, piston rings or another path. Results depend on the test procedure.
D
Damper / shock absorber / strut
Steering and suspension
A damper controls suspension motion. A suspension strut also acts as a structural part of the wheel-location arrangement. A spring supports load; it does not do the same job as the damper.
DCT — Dual-Clutch Transmission
Systems
A transmission with two independently controlled clutches serving separate gear paths. It can prepare the next gear before transferring drive between the clutches. Dual-clutch is different from a twin-disc clutch.
DEF / AdBlue
Engine and exhaust
DEF means Diesel Exhaust Fluid, a specified aqueous urea solution used by many SCR systems. AdBlue is a registered trade name for this type of fluid. It belongs in its dedicated tank, not the diesel fuel tank.
Diagnosis / diagnostic trouble code (DTC)
Electrical and diagnostics
Diagnosis is the process of testing to identify a fault's cause. A DTC is a code stored by a control module. A code identifies a detected problem or circuit; it does not, by itself, prove that one particular component must be replaced. DTC and DCT mean different things.
Diagnostic tester / ST5
Electrical and diagnostics
A scan tool communicates with supported vehicle control modules to read faults and data or run available service functions. ST5 is a diagnostic-tool designation in the GTE catalog. Coverage depends on the actual model, year, module and tool version.
Diaphragm spring
Clutch
The spring element in many pressure plates that produces clamping force and is acted on by the release mechanism. Finger wear, distortion or damage can affect release and engagement.
Differential
Gearbox
A gear assembly that distributes drive to the wheels while allowing them to rotate at different speeds when cornering.
DL501 / 0B5
Systems
Designations associated with an Audi longitudinal seven-speed dual-clutch transmission family. This family differs from the R8/Huracán DL800 and Getrag 7DCL750. Confirm the actual transmission code and component number before treating a clutch or circuit board as compatible.
DL800 transmission
Systems
A Graziano/Dana seven-speed dual-clutch transaxle used in applications including the Lamborghini Huracán and Audi R8. It is a different transmission family from the Getrag 7DCL750; parts and procedures are not interchangeable merely because both are DCTs.
DOHC / SOHC — Double / Single Overhead Camshaft
Engine and exhaust
Describes the camshaft arrangement above the cylinder head: two camshafts per head for DOHC or one for SOHC. These abbreviations alone do not specify the number of valves per cylinder.
DPF — Diesel Particulate Filter
Engine and exhaust
Traps diesel exhaust particles. Regeneration burns accumulated soot under controlled conditions; it does not remove all noncombustible ash. A blocked filter requires diagnosis of the cause.
Dry clutch / wet clutch
Clutch
A dry clutch operates without its friction surfaces being immersed in oil. A wet clutch uses oil for cooling and lubrication. Each requires the correct materials and service procedures.
Dry-fill / service-fill quantity
Fluids
Dry-fill quantity concerns a system emptied or assembled under specified conditions; a routine service may leave fluid in internal passages or coolers. The two quantities may differ. Final level must be checked using the correct temperature and procedure.
DSG — Direct Shift Gearbox
Systems
Volkswagen Group terminology for a dual-clutch gearbox. Different DSG families use different designs, clutch types and fluids. DSG is not sufficient identification for ordering a valve body, sensor, clutch or oil.
Dual-mass flywheel (DMF)
Clutch
A flywheel assembly with two masses and a damping mechanism intended to reduce torsional vibration. It differs from a solid flywheel and requires design-specific inspection and service decisions.
DuoSelect — Maserati
Systems
Maserati’s automated manual transmission designation on applicable Quattroporte models. It uses an electro-hydraulic shift system and a clutch operated without a driver clutch pedal. The Quattroporte Automatica uses a different automatic transmission arrangement. Model year and VIN must be checked rather than assuming all Quattroporte gearboxes are DuoSelect.
Duty cycle
Electrical and diagnostics
The proportion of time a device is energized during a defined period. For a controlled solenoid, this may describe the electrical command; for a pump, it may describe running time.
E
E-Diff — Electronic differential control
Hydraulics
A system that electronically controls differential locking behavior to influence traction and handling. It is distinct from the transmission's gear-selection mechanism.
E-Gear — Lamborghini
Systems
Lamborghini’s name for the electronically controlled automated manual system used on applicable Gallardo and Murciélago models. Hydraulic components operate the clutch and select gears. E-Gear is a product name, rather than a universal expanded acronym. The pump, accumulator, actuator, hoses, clutch and gearbox are distinct parts of the system.
EBD — Electronic Brake-force Distribution
Braking and safety
Adjusts the distribution of braking force between wheels or axles to suit operating conditions. It commonly works through the ABS hardware.
ECM / PCM — Engine / Powertrain Control Module
Electrical and diagnostics
ECM usually identifies the engine controller. PCM refers to a powertrain controller whose responsibilities can include engine and transmission functions. Naming and module arrangements vary.
ECT — Engine Coolant Temperature
Engine and exhaust
A temperature measurement used for engine management and cooling control. An ECT sensor fault is different from a confirmed overheating condition.
ECU — Electronic Control Unit
Electrical and diagnostics
A general term for an electronic controller. In engine-related discussions, ECU commonly means Engine Control Unit. The transmission controller may be called a TCU or TCM.
EFI — Electronic Fuel Injection
Engine and exhaust
Uses electronic control to meter fuel through injectors. EFI is a broad description that includes different injection arrangements.
EGR — Exhaust Gas Recirculation
Engine and exhaust
Returns a controlled amount of exhaust gas to the engine intake or combustion process to influence combustion temperature and reduce nitrogen-oxide formation. The valve and cooler are separate possible components.
EGT — Exhaust Gas Temperature
Engine and exhaust
The temperature of exhaust gas at a specified measurement location. It may be monitored for engine protection and exhaust-treatment control.
Electro-hydraulic pump / power unit
Hydraulics
A pump produces hydraulic flow; the system develops pressure against resistance. A power unit may include the pump, motor, reservoir, accumulator and related controls, depending on the application. Check the listing for the supplied assembly.
Electrovalve (EV)
Hydraulics
Another name for an electrically controlled hydraulic valve, usually a solenoid valve. It opens, closes or meters a fluid passage. Similar-looking valves may have different functions and are not automatically interchangeable.
EPB — Electric Parking Brake
Braking and safety
An electrically operated parking brake. It is separate from the transmission’s Park lock; replacing rear brake parts may require a vehicle-specific service mode.
EPC — Electronic Power Control
Electrical and diagnostics
A warning or system term used in some Volkswagen Group applications for electronic engine/power control. It does not identify one failed part. The vehicle’s stored faults and operating symptoms must be checked.
EPS — Electric Power Steering
Steering and suspension
Steering assistance provided by an electric motor under electronic control. An EPS rack differs from a hydraulically assisted rack and may require model-specific coding, initialization or calibration after replacement.
ESP / ESC — Electronic Stability Program / Control
Braking and safety
Helps counter skidding by comparing the driver’s intended direction with vehicle motion and adjusting individual brakes and engine torque. ESP is Bosch’s name; ESC is the general term.
ETC — Electronic Throttle Control
Electrical and diagnostics
Electronic control of the engine throttle using sensors, a controller and an actuator. The abbreviation must be read in context. In ordinary writing, “etc.” means “and so on”; it is not a part name.
EV / BEV — Electric Vehicle / Battery Electric Vehicle
Hybrid and electric
EV commonly means electric vehicle; BEV specifically identifies a battery-powered electric vehicle. In hydraulic repair literature, EV can instead mean electrovalve. Read the system context.
EVAP — Evaporative Emission Control
Engine and exhaust
Captures and controls fuel vapor rather than letting it escape directly to the atmosphere. Components can include a charcoal canister, purge valve and vent valve.
EVF — clutch electrovalve designation
Hydraulics
In applicable Italian automated-manual hydraulic diagrams, EVF identifies the clutch-control electrovalve, associated with frizione (clutch). An EVF hose or line refers to that circuit in the relevant product listing. Confirm routing, fittings and application; it is not a universal hose size or part number.
Exchange unit
Ordering and service
A supplied assembly associated with return of an eligible used core under the listing’s conditions. Core approval, deposit terms and deadlines depend on the specific offer.
External leakage
Hydraulics
Fluid escaping outside the intended sealed circuit. The visible drip location may differ from the source, so the leak should be traced before parts are selected.
F
F1 — Ferrari Formula 1-derived paddle-shift system
Systems
F1 means Formula 1. On applicable Ferrari road cars, the F1 designation refers to an electronically controlled, hydraulically operated manual gearbox with steering-wheel shift controls. The system operates the clutch and gear selection for the driver. It is not a Formula 1 race gearbox, and not every paddle-shift Ferrari uses this older automated-manual architecture.
F1-S / SuperFast terminology
Systems
Performance-shift wording used in particular Ferrari applications and GTE service descriptions. The meaning depends on the model or package. It does not by itself identify a universal actuator, software version or DCT. Read the exact product scope and application.
Final drive
Gearbox
The reduction gear arrangement between the transmission output and driven wheels, often integrated with the differential. It is distinct from the selectable gear ratios.
Fitment / compatibility
Ordering and service
Whether a part is suitable for the exact vehicle and assembly configuration. Confirm using the VIN, transmission identification, part number, revision and relevant modifications; appearance alone is not enough.
Flushing / contamination control
Fluids
Cleaning or exchanging fluid to reduce unwanted particles or incompatible residues using an appropriate procedure. Contaminated lines, reservoirs or coolers can affect a repaired assembly after installation.
Flywheel
Clutch
A rotating component attached to the engine that helps smooth rotation and provides a drive connection to the clutch. Inspection, resurfacing and balancing are different services and depend on flywheel design and condition.
Flywheel resurfacing
Clutch
Machining or finishing an eligible flywheel friction surface to the required geometry and condition. Some flywheel designs have restrictions. Surface finish, step dimensions and remaining thickness must be checked.
Friction coefficient
Measurements
A measure of friction behavior between contacting materials under particular conditions. It varies with material, temperature and operating state. A friction coefficient alone is not a complete clutch torque-capacity rating.
Friction material
Clutch
The lining that creates friction to transmit torque in a clutch. Material choice affects engagement characteristics, heat behavior and wear; suitability depends on the application and operating conditions.
Front suspension lift / nose lift
Steering and suspension
A system that temporarily raises the front of an applicable vehicle for clearance. Its pump, motor, valves, pressure controls and relay can be separate service items. It is distinct from the transmission hydraulic system.
G
Gasket / seal / O-ring
Hydraulics
Parts that prevent unwanted fluid leakage or separate fluid passages. A gasket usually seals a joint between surfaces; seals and O-rings suit specific static or moving interfaces. Replacing seals does not automatically include sensors, valves or gears.
GDI / DI — Gasoline Direct Injection / Direct Injection
Engine and exhaust
Fuel is injected directly into the combustion chamber. GDI specifies gasoline; DI can also refer to diesel injection. The pump, injectors and pressure requirements are application-specific.
Gear engagement sleeve
Gearbox
A sliding component that locks a selected gear to its shaft so it can transmit drive.
Gear oil / hydraulic fluid / DCT fluid
Fluids
Fluids with different jobs and specifications. Gear oil lubricates gears and bearings; hydraulic fluid operates pressure-controlled components; a DCT fluid may also serve wet clutches. Some transmissions have separate circuits. Never choose or mix fluids by color or a general system nickname.
Gear ratio
Measurements
The relationship between input and output rotational speeds. Different ratios change the balance between wheel torque and vehicle speed.
Gear selector / shift rail
Gearbox
Parts that guide and transmit gear-selection movement inside or alongside a gearbox. Actuator movement must correctly operate the selector mechanism; an electrical command alone does not prove a gear engaged.
Genuine / OE / OEM / aftermarket
Ordering and service
Genuine usually refers to the vehicle brand’s supplied part; OE means original equipment; OEM means original equipment manufacturer; aftermarket refers to the replacement market outside the vehicle maker’s original supply channel. Listing usage varies, so verify the stated manufacturer and source rather than relying on a label alone.
Getrag / Magna
Systems
Supplier names encountered in transmission identification and parts listings. Getrag developed transmission families including the 7DCL750. A manufacturer name alone does not identify a gearbox version, fluid specification or compatible replacement part.
Getrag 7DCL750 / 7DCL800
Systems
Getrag dual-clutch transmission designations used in high-performance applications. Confirm the exact transmission version and part number: shared family names do not establish component compatibility. See SAP and CCP for the hydraulic assemblies discussed in 7DCL750 repairs.
GPF / OPF — Gasoline / Otto Particulate Filter
Engine and exhaust
A particulate filter used on applicable gasoline engines to reduce particle emissions. It serves a different function from a catalyst, even when components are combined.
Graziano / Dana
Systems
Supplier names found on several high-performance manual, automated manual and dual-clutch transmission applications. Sharing a supplier does not mean two transmissions share parts. Use the gearbox identification and application-specific part number.
Ground / earth / voltage drop
Electrical and diagnostics
Ground is the circuit’s electrical reference and return path. Voltage-drop testing measures voltage lost across connections or components while current flows, helping locate excessive resistance.
H
Hall-effect sensor
Electrical and diagnostics
An electronic sensor that responds to a magnetic field and may measure speed or position. It differs from a resistive potentiometer; testing must suit the sensor design.
Engine and exhaust
Pipes or passages collecting exhaust gas from the cylinder head and directing it downstream. Fitment depends on the engine, chassis and connected exhaust components. A performance label alone does not establish road-use approval.
HEV / PHEV / MHEV
Hybrid and electric
HEV means Hybrid Electric Vehicle; PHEV means Plug-in Hybrid Electric Vehicle; MHEV means Mild Hybrid Electric Vehicle. Their electric-driving and charging capabilities differ by design.
High-pressure hose / return hose
Hydraulics
A high-pressure hose carries fluid in a pressurized working circuit. A return hose routes fluid back toward the reservoir or lower-pressure side. They can require different construction and fittings and must not be interchanged simply because their diameters look similar.
HP / bhp / PS / kW
Measurements
Power units or measurement descriptions. HP is horsepower, bhp commonly describes brake horsepower, PS is metric horsepower and kW is kilowatts. Measurement standard and location matter; these labels should not be mixed without clarification.
HPFP — High-Pressure Fuel Pump
Engine and exhaust
Raises fuel pressure for the injection system. It is different from the low-pressure supply pump in or near the tank. A pressure fault requires testing of the complete supply and control system.
HV — High Voltage
Hybrid and electric
Identifies the higher-voltage electrical system used in electric and hybrid powertrains. Work on this system requires the specified isolation procedures, training and equipment.
Hydraulic circuit
Hydraulics
The connected passages, pipes, hoses and components through which hydraulic fluid flows to operate a system.
Hydraulic control unit (HCU)
Hydraulics
An assembly that controls hydraulic pressure and directs fluid to working components. It may contain valves, sensors and passages. HCU, power unit and actuator may refer to different assemblies in different listings; compare the part number and included components.
Hydraulic power unit (HPU)
Hydraulics
An assembly that provides hydraulic supply, commonly using a pump and motor with associated reservoir, accumulator or controls. It supplies the energy needed by the actuator; it is not automatically the gear actuator itself.
Hydraulic pressure sensor
Hydraulics
Measures fluid pressure and sends an electrical signal to a controller. A pressure-related fault can involve the sensor, wiring or actual hydraulic pressure, so testing is needed.
I
IAT — Intake Air Temperature
Engine and exhaust
The temperature of air entering the engine, measured by a separate sensor or one integrated into another assembly. The controller uses it to adjust engine operation.
ICE — Internal Combustion Engine
Engine and exhaust
An engine that burns fuel inside its cylinders to produce mechanical power. Gasoline and diesel engines are common examples.
Ignition coil / spark plug
Engine and exhaust
The coil generates the high voltage needed for the spark plug to ignite the mixture in a spark-ignition engine. They are separate components with different service requirements.
Impeller
Cooling
The rotating part of a pump that moves fluid. Its condition, attachment and design affect circulation. A pump can have a functioning drive while suffering an internal impeller problem.
Gearbox
The input shaft receives drive into the gearbox. The output shaft delivers drive from the gearbox toward the final drive or wheels.
Gearbox
Rotational-speed measurements at different locations in a drivetrain. Comparing them helps the controller assess gear ratio, clutch slip and operation. A fault in one speed signal is not automatically a failed clutch.
Inspection report / estimate / additional work
Ordering and service
An inspection report records findings; an estimate sets out proposed work and charges. Additional parts or services should be identified in the applicable approved scope. A diagnostic finding is not automatically an included replacement.
Installation / removal and refitting (R&R)
Ordering and service
Labor to remove a component from the vehicle and install it or its replacement. This may be separate from a mail-in rebuild price. Fluids, bleeding, coding, calibration and road testing should be identified in the agreed scope.
Intercooler / charge-air cooler
Engine and exhaust
Cools compressed intake air after a turbocharger or supercharger. Designs may transfer heat to ambient air or to a liquid circuit. It is different from the engine radiator.
Clutch
A plate used between friction discs in certain multi-disc clutches. Its condition, flatness and movement affect engagement and release. A twin-disc assembly has more parts to assess than the friction linings alone.
Intermittent fault
Electrical and diagnostics
A problem that appears only sometimes, such as at a particular temperature or vibration level. Testing may need to reproduce those conditions; clearing codes alone does not repair it.
Internal leakage / bypass
Hydraulics
Fluid leaking between passages or past a sealing surface inside an assembly. It may reduce pressure or performance without producing visible fluid outside the unit.
Inverter / DC–DC converter
Hybrid and electric
An inverter in an electric drivetrain converts battery DC into controlled AC for the traction motor and supports reverse energy flow where designed. A DC–DC converter changes DC voltage levels, for example to supply the low-voltage electrical system.
ISO standards
Ordering and service
Standards published by the International Organization for Standardization. The applicable standard must be identified for a specific process or quality claim; mentioning ISO alone does not establish certification.
ISR — Independent Shifting Rods
Systems
Lamborghini’s automated manual transmission technology associated with the Aventador. Independent shift-rod operation enables rapid gear changes. ISR is not a dual-clutch gearbox; its clutch, hydraulics and gear-selection parts require the correct ISR-specific identification.
L
Lambda / O2 sensor
Engine and exhaust
An exhaust oxygen sensor helps the controller assess combustion mixture. Lambda compares the actual air–fuel ratio with the chemically balanced ratio for that fuel: 1 is balanced, below 1 is rich and above 1 is lean.
Launch control
Systems
A vehicle control function that coordinates engine and transmission operation during a rapid start from rest. Availability and operating limits depend on the vehicle.
LED — Light-Emitting Diode
Electrical and diagnostics
An electronic light source used in vehicle lamps. A replacement LED assembly must match the electrical interface, physical fit and application. An LED upgrade is not a transmission or engine control upgrade.
LH / RH / LHD / RHD / SX / DX
Ordering and service
LH and RH mean left-hand and right-hand; LHD and RHD describe driving position. In Italian parts references, SX means sinistra (left) and DX means destra (right). Confirm the catalog’s orientation and component illustration before ordering.
Limited-slip differential (LSD)
Gearbox
A differential that limits excessive speed difference between its outputs to help transfer drive when traction differs.
Electrical and diagnostics
A protective operating strategy used when a controller detects a condition that requires restricted operation. It may limit power, available gears or other functions. The warning describes a response, not the root cause.
LIN — Local Interconnect Network
Electrical and diagnostics
A vehicle communication network commonly used for relatively simple local devices, such as actuators and switches. LIN and CAN have different signaling and diagnostic requirements.
Live data / freeze-frame data
Electrical and diagnostics
Live data shows values reported during a diagnostic session. Freeze-frame data records selected operating information when a fault was stored. Both require interpretation against the correct conditions and specifications.
M
MAF — Mass Air Flow sensor
Engine and exhaust
Measures the mass of intake air so the engine controller can calculate fueling and other functions. It differs from a manifold-pressure sensor.
Manual / gated manual transmission
Systems
A gearbox in which the driver selects gears and normally operates a clutch pedal. Gated refers to a guide plate for the shift lever. A gated-conversion kit changes the driver controls and related systems according to its stated scope; it does not automatically replace or rebuild all gearbox internals.
MAP — Manifold Absolute Pressure sensor
Engine and exhaust
Measures intake-manifold pressure relative to a vacuum reference. Absolute pressure includes atmospheric pressure, so it differs from a gauge boost reading.
Master cylinder — clutch
Clutch
The cylinder that converts clutch-pedal movement into hydraulic pressure on applicable manual systems. It differs from the slave cylinder, which produces movement at the clutch.
MC Auto Shift — Maserati
Systems
A Maserati automatic-transmission control strategy used on applicable models with a conventional automatic gearbox. It is different from the electro-actuated MC Shift transaxle. Confirm the actual transmission before selecting a clutch, hydraulic actuator or rebuild package.
MC Shift — Maserati
Systems
Maserati’s performance-oriented electro-actuated gearbox designation on applicable GranTurismo models. It belongs to the automated manual family. MC Shift and MC Auto Shift are different transmission descriptions; the presence of steering-wheel paddles or an MC badge alone does not identify which transmission is fitted.
Mechanical seal — water pump
Cooling
A sealing arrangement that separates coolant from areas that should remain dry or separately lubricated. It differs from a simple external gasket. Leakage through a tell-tale opening can help reveal a sealing problem.
Mechatronics unit
Gearbox
A term for an assembly combining mechanical, hydraulic and electronic control functions. The components included vary by transmission; the term does not always mean the entire transmission computer and every hydraulic component.
MIL / CEL — Malfunction Indicator Lamp / Check Engine Light
Electrical and diagnostics
The engine/emissions warning lamp. It signals that the controller detected a relevant fault; read the stored codes and follow the vehicle’s guidance, especially if the lamp flashes.
Misfire
Engine and exhaust
A combustion event that fails or produces insufficient contribution. Causes can include ignition, fueling, air leaks or mechanical condition. A cylinder misfire code is a starting point for testing.
MT-1 / L140 transmission identification
Systems
Transmission designations encountered in Graziano gearbox service. They should not be treated as universal identifiers for all Ferrari, Lamborghini or Audi gearboxes. Match the actual unit identification, vehicle application and part number before ordering.
O
OBC — On-Board Charger
Hybrid and electric
Converts external AC electrical supply into suitable DC for charging the traction battery. It is distinct from a DC fast charger outside the vehicle.
OBD / OBD-II
Electrical and diagnostics
On-board diagnostics terminology. OBD-II defines standardized diagnostic functions, but a generic scanner may not access every manufacturer-specific transmission function, learning routine or fault detail.
Odd / even gear paths
Gearbox
The two gear groups controlled by a DCT's separate clutches. In the Ferrari Getrag 7DCL750 configuration, one path serves gears 1, 3, 5 and 7, and the other serves gears 2, 4, 6 and reverse. Loss of one group requires diagnosis of the relevant mechanical, hydraulic and electrical systems.
OEM / OEM-spec
Ordering and service
OEM means Original Equipment Manufacturer. OEM-spec describes a stated specification or operating target; it does not automatically mean a part was manufactured by the vehicle maker. Read the listing for the component's manufacturer and intended specification.
OEM-quality / OEM-style
Ordering and service
Descriptive claims about a replacement part’s intended quality or behavior. These phrases do not by themselves prove original-equipment manufacture or vehicle-brand approval. The listing should identify the actual part and applicable specification.
Oil cooler / heat exchanger
Cooling
Transfers heat between oil and another medium such as air or coolant. It can be affected by restrictions, external damage or internal leakage. A replacement cooler must match the circuit and application.
Oil filter / strainer
Fluids
Components that remove or screen contaminants from a fluid supply. A strainer and a fine filter may perform different jobs. Replacing a filter does not remove every contaminant already distributed through a damaged system.
Open circuit / short circuit
Electrical and diagnostics
An open circuit is an interrupted electrical path. A short circuit is an unintended low-resistance connection. Diagnostic wording describes the detected circuit condition, not automatically the exact failed component.
Electrical and diagnostics
An oscilloscope displays how an electrical signal changes over time. Waveform testing can reveal intermittent faults or timing relationships that a simple resistance check misses.
OTO — One-to-One / GTE program naming
Systems
OTO is used in Ferrari One-to-One model/program terminology and in the name of GTE’s Ferrari 360 OTO clutch program. These references must be read in context. The GTE 360 OTO clutch configuration is a specific product program, not a generic synonym for every dual-clutch transmission.
P
Paddle shift
Systems
Steering-wheel or steering-column controls that request gear changes. Paddles can be fitted to automated manuals, DCTs and conventional automatics. They describe the driver interface, not the transmission architecture.
Park lock / parking pawl
Gearbox
A mechanism that mechanically locks part of the transmission to prevent rotation in the park position on applicable designs. It is separate from a service brake or parking brake.
Part number (PN / P/N / MPN)
Ordering and service
PN or P/N means part number; MPN means manufacturer part number. Numbers, suffix letters and revisions help identify components. Similar numbers do not guarantee interchangeability.
PCV — Positive Crankcase Ventilation
Engine and exhaust
Controls ventilation of combustion gases that pass the piston rings into the crankcase, commonly routing them back to the intake. Faults can affect oil leakage, oil consumption and running quality.
PDK — Porsche dual-clutch transmission
Systems
PDK stands for Porsche-Doppelkupplungsgetriebe, meaning Porsche dual-clutch transmission. Porsche uses different PDK versions across its vehicles. A part labeled DSG, S tronic or DL501 is not automatically a Porsche PDK fitment; verify the exact gearbox and part number.
PEGA Clutch®
Clutch
GTE's clutch component and friction-lining brand. The selected lining and rebuild specification determine the intended application. A PEGA clutch lining service does not imply that every component in the drivetrain is a PEGA product.
PFI / MPI — Port Fuel Injection / Multi-Point Injection
Engine and exhaust
Fuel is injected into the intake ports before the intake valves. Multi-point generally means separate injection points for individual cylinders. Some engines combine port and direct injection.
PID — Parameter ID / proportional-integral-derivative
Electrical and diagnostics
On a scan tool, PID commonly identifies a data parameter. In control engineering, PID means proportional-integral-derivative control. The same letters have different meanings in these contexts.
PIS — Clutch engagement reference
Clutch
A calibration setting used on applicable Ferrari F1 and Maserati automated manual systems to establish the onset of clutch engagement. Correct adjustment depends on the model, control software and clutch condition; there is no single value suitable for every vehicle. See bite point.
Potentiometer / position sensor
Electrical and diagnostics
A position sensor reports the location of a component such as a gear selector or clutch actuator. A potentiometer is one type of position sensor; other designs use different sensing technology.
Pre-charge — accumulator
Hydraulics
The gas pressure established in an accumulator before hydraulic operating pressure is applied. Pre-charge is different from the system’s running hydraulic pressure. The correct value and serviceability depend on the accumulator design.
Pressure plate
Clutch
The part of a clutch assembly that applies clamping force to the friction disc or discs.
Pressure relief valve
Hydraulics
A valve that limits pressure by opening a flow path when its operating conditions are met. It differs from a pressure sensor, which measures pressure, and from a pump, which moves fluid.
Pressure retention / leak-down
Hydraulics
How well a hydraulic circuit holds pressure over time under defined conditions. Pressure decay can reflect leakage, commanded operation, temperature changes or accumulator behavior. Interpretation requires the correct test conditions.
Priming / pressure build-up
Hydraulics
The process of establishing fluid supply and operating pressure before or during system use. Slow pressure build-up can have several causes, including supply, pump, accumulator or leakage problems; it does not identify one failed part by itself.
Proportional valve / on-off valve
Hydraulics
A proportional valve meters a controlled hydraulic response; an on-off valve primarily opens or closes a path. Similar external appearance does not prove identical internal function or interchangeability.
PTU — Power Transfer Unit
Systems
A unit that transfers drive within an all-wheel-drive system. On the Ferrari FF and applicable GTC4Lusso models, the front-drive PTU is a separate assembly from the rear DCT. A PTU repair and a DCT repair are separate service scopes.
Pump head
Hydraulics
The fluid-moving section of a pump assembly. It may be serviced separately from the electric motor depending on the design and product scope.
Pump motor
Hydraulics
The electric motor that drives a pump. The motor and pump head have separate functions: a sound motor does not prove the pump can produce the required flow, and a pump problem does not automatically mean the motor is faulty.
PWM — Pulse-Width Modulation
Electrical and diagnostics
A method of controlling average electrical output by switching a signal on and off with a varying duty cycle. It is used in many motor and solenoid control applications.
R
R tronic — Audi R8
Systems
Audi’s automated manual transmission designation on applicable earlier R8 models. It has hydraulically operated clutch and gear selection. R tronic and S tronic use different transmission architectures, so the names must not be used interchangeably when ordering parts.
R tronic / S tronic — Audi
Systems
R tronic refers to the automated manual system used in applicable earlier R8 models. S tronic is Audi's dual-clutch transmission name. These systems require different parts and procedures.
Rebuild / refurbishment service
Ordering and service
Work performed on a used assembly to restore the functions covered by the agreed service. It may involve disassembly, inspection, cleaning, selected repairs or replacement parts, reassembly and testing. The listing and approved estimate define what is included; the word rebuild does not mean every internal part is replaced.
Rebuild service versus replacement assembly
Ordering and service
A rebuild service normally involves sending an existing component for the agreed work. A replacement assembly is a supplied unit in the condition stated by the listing. Exchange/core requirements, included hardware and installation are separate details to confirm.
Rebuilt / remanufactured / refurbished
Ordering and service
Terms for work on an existing component. Their scope varies by supplier and product. Ask what is inspected, renewed, repaired and tested; none of the words alone means every internal component is new.
Regenerative braking / regen
Hybrid and electric
Uses an electric machine to slow the vehicle while recovering energy to the battery. Available regeneration depends on battery and vehicle conditions; friction brakes remain part of the braking system.
Relay / fuse
Electrical and diagnostics
A relay switches an electrical circuit in response to a control signal; a fuse protects a circuit against excessive current under its specified conditions. A failed fuse or relay can be a symptom of another fault and should not be repeatedly replaced without diagnosis.
Release travel / clearance
Clutch
The movement and available space needed to disengage a clutch properly. Incorrect travel or clearance can cause incomplete release or other operating problems. Use the specification for the exact assembly.
Relining
Clutch
Replacing friction material on a reusable clutch component after inspection. Related pressure-plate, flywheel, bearing or sensor work is included only when stated in the service scope.
Repair kit / seal kit / complete assembly
Ordering and service
A kit contains its listed components for a particular job. A seal kit is not a complete rebuild kit unless explicitly stated. Complete assembly also requires an itemized scope: sensors, hoses, brackets or programming may still be separate.
Reservoir
Hydraulics
A container that stores fluid for a hydraulic system and allows supply to the pump. Reservoir level, venting and contamination must be assessed according to the correct procedure.
Resistance / ohms (Ω)
Electrical and diagnostics
Electrical resistance is measured in ohms. A coil resistance reading is one test only: correct resistance does not prove that a valve moves correctly or meters fluid properly under pressure and temperature.
Rev-matching
Gearbox
Adjusting engine speed to suit the next gear, particularly during a downshift.
RPM — Revolutions Per Minute
Measurements
A measure of rotational speed. Engine, gearbox-shaft and wheel RPM are different values connected by the active ratios and clutch state.
Runout / flatness
Clutch
Runout is measured deviation as a part rotates relative to a reference. Flatness describes how closely a surface lies in one plane. Excessive deviation can affect rotating assemblies, friction contact or sealing.
S
S tronic — Audi
Systems
Audi’s name for dual-clutch transmissions. Several different gearbox families carry the S tronic name. It identifies the transmission type, but not one universal gearbox or parts set. The R8’s DL800 and the 0B5/DL501 are distinct applications.
SAP unit — Getrag gear-selection hydraulic assembly
Hydraulics
Commonly called the Shift Actuating Panel in repair terminology; technical literature also uses Synchronizer Actuation Plate. In the Getrag 7DCL750 context, it operates the mechanisms that engage the selected gears. In plain language: the SAP moves the gear-selection mechanism, while the CCP controls clutch application. Servicing the SAP does not automatically include gears, synchronizers, the clutch pack or the CCP.
SCR — Selective Catalytic Reduction
Engine and exhaust
An exhaust-treatment process that reduces nitrogen oxides using a catalyst and a reducing agent. Many diesel systems use DEF/AdBlue dosing for this purpose.
Selespeed — Alfa Romeo
Systems
Alfa Romeo’s name for an electronically controlled, electro-hydraulically operated manual transmission on applicable models. The system operates the clutch and shifts gears for the driver. Selespeed is a system name, not a generic name for every automatic gearbox. Shared technology with other automated manuals does not make their parts or fluids universally interchangeable.
Sequential shifting
Systems
Selecting the next higher or lower gear in sequence. The term can describe the controls of a road-car automated manual, but it does not necessarily mean the internal design is the same as a racing sequential gearbox.
Shift fork
Gearbox
A mechanical component that moves a selector sleeve or related engagement mechanism to select a gear.
Slave cylinder / concentric slave cylinder (CSC)
Clutch
A hydraulic cylinder that converts fluid pressure into clutch-release movement. A concentric slave cylinder surrounds the gearbox input shaft and may integrate the release bearing. Listing scope determines whether the bearing, cylinder and sensor are included.
SMG / SMG II / SMG III — BMW
Systems
BMW terminology for its automated manual gearboxes. BMW M literature uses Sequential M Gearbox; Sequential Manual Gearbox is also used in service terminology. SMG II and SMG III identify different generations. A hydraulic pump-system rebuild is separate from a clutch replacement or complete gearbox rebuild.
SOC / SOH — State of Charge / State of Health
Hybrid and electric
SOC estimates how full a battery is. SOH estimates condition or capability relative to a reference. A fully charged battery can still have reduced health or capacity.
Software adaptation reset
Electrical and diagnostics
Clearing learned control values with a diagnostic procedure when required. A reset and the subsequent learning process are separate steps; a reset alone does not complete a repair.
Solenoid valve
Hydraulics
An electrically actuated valve that controls hydraulic fluid flow or pressure. See electrovalve (EV).
Speed sensor — gearbox / clutch
Clutch
Measures rotational speed at a specified shaft or component so the controller can monitor drive and shifting. Gearbox shaft, engine/input and clutch-related speed signals are distinct; the correct sensor must be identified for the fault and transmission version.
Sportshift / Sportshift II / Sportshift III
Systems
Aston Martin’s names for generations of automated manual transmission used in applicable models. Sportshift systems are associated with ASM terminology. Different generations have different components, software and procedures; identify the vehicle and unit before ordering. Sportshift is not a blanket description of every Aston Martin automatic transmission.
SRS — Supplemental Restraint System
Braking and safety
The airbag and associated restraint-control system, which may include seat-belt pretensioners. A warning identifies a system fault requiring diagnosis, not necessarily a failed airbag.
SSG — Seamless Shift Gearbox
Systems
McLaren’s name for its dual-clutch transmission. The seven-speed Graziano units in applicable McLaren models have their own parts and service procedures. SSG describes a transmission system; it does not make every McLaren gearbox version interchangeable.
Stage / service level
Ordering and service
A package name whose meaning depends on the particular product and service. A clutch Stage 1 and a transmission Stage 1 do not automatically include the same work or imply the same performance rating.
Stage 1 — GTE Getrag 7DCL750 service
Ordering and service
Teardown and inspection only. Additional parts, electronics and repair services are extra, including gearbox or clutch-related speed sensors, electrovalves, gears, seals, pumps, pressure sensors, gaskets, and refurbishment of the SAP and CCP hydraulic units. Refer to the product listing and approved estimate for the agreed scope.
Steering rack — hydraulic
Steering and suspension
A steering gear that converts steering input into side-to-side motion with hydraulic assistance. The rack, pump, hoses and control components are separate items. A rack rebuild is not a rebuild of the entire steering system.
Steering-angle sensor / alignment
Steering and suspension
The sensor reports steering position electronically; wheel alignment sets the physical wheel geometry. Sensor calibration and wheel alignment are different procedures that may both be relevant after steering work.
STFT / LTFT — Short-Term / Long-Term Fuel Trim
Engine and exhaust
Fueling corrections applied by the engine controller. Short-term trim responds quickly; long-term trim represents learned correction. The sign and magnitude help diagnosis but do not identify a failed part by themselves.
Superseded part number / revision
Ordering and service
A supersession is a replacement reference issued by a supplier or manufacturer; a revision identifies a changed version. Compatibility can depend on accompanying parts or software. Confirm the authorized replacement chain for the specific vehicle.
Suspension pump / steering pump
Steering and suspension
A pump supplying the designated vehicle hydraulic circuit. Some vehicle arrangements share a supply; others do not. The product number and circuit identify the correct application, not the word pump alone.
Synchronizer (synchro)
Gearbox
A gearbox mechanism that helps match rotational speeds before a gear is engaged. Hydraulic control repairs do not automatically repair worn or damaged synchronizers.
T
TCS / ASR — Traction control
Braking and safety
TCS means Traction Control System. ASR, from the German Antriebsschlupfregelung, is another traction-control designation. These systems limit excessive driven-wheel spin using braking and/or power reduction.
TCT — Twin Clutch Transmission
Systems
Alfa Romeo’s dual-clutch transmission designation. Applicable Alfa TCT systems use two clutch paths to prepare and execute gear changes. TCT differs from the earlier Selespeed automated manual system. A TCT shift-actuator service covers the stated actuator work, not automatically both clutches or all gearbox internals.
TCU / TCM — Transmission Control Unit / Module
Electrical and diagnostics
The computer that manages transmission operation using sensor information and commands to valves or actuators. It is not the same component as the clutch pack or a hydraulic valve body.
TCU circuit board / conductor plate
Electrical and diagnostics
An electrical assembly carrying circuits, connections or sensors in the relevant transmission-control design. Replacing a board is different from replacing all hydraulic valves or the entire mechatronics assembly.
TCU software upgrade / bypass module
Electrical and diagnostics
A software upgrade changes compatible controller software; a bypass module performs the specific interface or control function described by its supplier. Neither should be assumed to repair worn clutch hardware or failed hydraulics.
TDC / BDC — Top / Bottom Dead Center
Engine and exhaust
The piston’s highest and lowest travel positions. Timing specifications may refer to degrees before or after TDC.
Teardown and inspection
Ordering and service
Disassembling an assembly to examine its condition and identify required work. It is an assessment stage, not a promise that all repairs or replacement parts are included in the inspection price.
Thermal capacity / heat fade
Measurements
Thermal capacity concerns the heat an assembly can absorb or manage; heat fade describes reduced performance under elevated temperature. Material choice, assembly size, cooling and use all matter.
Thermal load
Measurements
The heat a component must absorb or dissipate during operation. Excessive clutch slip can increase thermal load.
Thermostat
Cooling
A temperature-responsive valve that regulates coolant routing as the engine warms and operates. It is separate from the coolant pump and temperature sensor.
Throw-out bearing (TOB) / release bearing
Clutch
The bearing that transfers release force to the rotating clutch mechanism. Some designs incorporate a hydraulic slave cylinder. Rebuilding this component does not automatically include the clutch disc or pressure plate.
Thrust washer / shim / end float
Gearbox
A thrust washer supports axial load or provides a wearing surface; a shim adjusts spacing. End float is permitted axial movement. Incorrect location or thickness can affect gearbox alignment and durability.
Tolerance / clearance / interference fit
Measurements
Tolerance is the permitted variation in a dimension. Clearance is a designed gap; an interference fit uses overlapping nominal dimensions to create a tight fit. Correct assembly requires the relevant component specifications.
Torque — Nm / lb-ft
Measurements
Torque is twisting force, commonly expressed in newton-metres or pound-feet. Engine torque delivery is central to clutch selection. A bolt-tightening torque specification is a different use of the same physical quantity.
Torque capacity
Measurements
The torque a component is designed or rated to transmit under specified conditions. Heat, wear, calibration and use can affect real-world performance; a stated rating is not an unlimited guarantee.
Torque-to-yield / TTY fastener
Measurements
A fastener tightened using a procedure designed to produce controlled permanent stretch. Replacement and tightening requirements come from the manufacturer; an angle-tightening step alone does not prove every bolt is TTY.
TPMS — Tire Pressure Monitoring System
Braking and safety
Monitors tire pressure directly with pressure sensors or indirectly through wheel behavior, depending on the design. Resetting the system does not correct an actual pressure loss.
TPS — Throttle Position Sensor
Engine and exhaust
Reports throttle-valve position. In electronic throttle systems it helps the controller check and regulate throttle movement.
Transaxle
Gearbox
A transmission and final-drive/differential arrangement combined in one assembly.
Turbocharger
Engine and exhaust
Uses exhaust-gas energy to drive a compressor that supplies pressurized intake air. A turbocharger rebuild concerns the turbo assembly under the stated scope; oil supply, intake leaks, exhaust restrictions and engine faults can also affect operation.
Turnaround time / lead time
Ordering and service
Turnaround generally describes service processing after the stated start conditions are met; lead time describes the expected time before supply or completion. Shipping, inspection approval and additional parts can affect the total elapsed time.
Twin-disc clutch
Clutch
A clutch using two friction discs operated together for one drive connection. It is different from a DCT, which uses two independently controlled clutch paths.
Twin-turbo / forced induction
Engine and exhaust
Twin-turbo describes an engine using two turbochargers; forced induction includes turbocharging or supercharging. Increased engine output changes drivetrain demands, but the actual torque curve and usage determine clutch selection.
V
Valve body
Hydraulics
An assembly of hydraulic passages and valves that directs and regulates fluid within a transmission or actuator system.
Valved exhaust
Engine and exhaust
An exhaust system with valves that change the gas path and sound behavior under specified conditions. The valves may use vacuum or electric actuation. A system described as valved is not necessarily supplied with every controller or actuator.
VIN / model year (MY)
Ordering and service
VIN means Vehicle Identification Number; MY means model year. They help determine equipment and production variations. Registration year alone may not identify the correct part.
Viscosity / oil grade
Fluids
Viscosity describes a fluid’s resistance to flow under specified conditions. An oil grade alone does not establish its complete additive chemistry or suitability for clutches, seals or hydraulic controls.
Viscous coupling / viscous coupler
Gearbox
A coupling that transfers torque through the behavior of viscous fluid between internal elements. Its fluid specification, fill quantity and internal condition affect operation. It differs from an electronically controlled clutch-type differential.
Voltage / current — V / A
Electrical and diagnostics
Voltage, measured in volts, is electrical potential difference; current, measured in amperes, is electrical flow. A normal unloaded voltage reading does not prove a circuit can supply the required current.
VVT — Variable Valve Timing
Engine and exhaust
Changes valve timing to suit engine speed and load. Systems can use oil-controlled camshaft adjusters or other designs; VVT does not necessarily mean variable valve lift.
W
Warranty / coverage
Ordering and service
The applicable written warranty defines covered work, duration, exclusions and claim steps. A glossary definition does not expand those terms. Review the product’s linked warranty and the approved estimate.
Wastegate / boost actuator
Engine and exhaust
The wastegate regulates exhaust flow through or around the turbocharger turbine to control boost. Its actuator moves the mechanism. A boost fault can involve control, leaks or other components, not just the turbocharger itself.
Water pump / coolant pump
Cooling
Circulates engine coolant through the cooling circuit. A pump rebuild may address the pump’s seals, bearings or other eligible components under the stated scope. It does not automatically include the radiator, thermostat or the entire cooling system.
Wear limit
Measurements
The maximum permitted wear or minimum acceptable dimension for a specific component under the applicable specification.
Weep hole / tell-tale opening
Hydraulics
An opening designed to reveal leakage or allow drainage at a particular assembly location. The source and fluid must be identified before deciding which seal or component needs repair.
Wiper motor
Electrical and diagnostics
The electric motor that drives the windshield-wiper linkage or mechanism. The motor, linkage, switches and control electronics are separate possible fault areas.
Wiring harness / connector
Electrical and diagnostics
The wiring and connection points linking components. Corrosion, pin damage, poor contact or insulation faults can cause symptoms that resemble a failed sensor or actuator.
WOT — Wide Open Throttle
Measurements
A condition in which the throttle is fully open. It is an operating term, not a recommendation to perform a full-load test on a faulty vehicle.
PEGA Clutch® — Stages 1–5, engagement feel and power capacity
PEGA clutch stages describe friction-lining configurations and their intended driving character. Choose a stage for your vehicle, engine output and use, as well as the engagement feel you want.
These are clutch performance stages. They are separate from GTE transmission service levels: PEGA Stage 1 is an organic clutch-lining specification, whereas GTE Getrag 7DCL750 Stage 1 means teardown and inspection only.
Quick comparison: soft to harsh engagement
Comfort scale: 5 = softest / most comfort-oriented; 1 = most aggressive / least comfort-oriented. The descriptions below translate PEGA’s published comfort scale into plain language. They describe engagement character, not measured pedal effort. Actual feel depends on the clutch assembly, vehicle, installation, break-in and calibration.
PEGA clutch lining and comfort guide
| Stage |
Lining configuration |
Comfort / feel |
Intended driving balance |
| 1 |
Full FX4C-SC Organic |
5/5 — softest, progressive, OEM-style |
80% regular / 20% sport |
| 2 |
FX4C-SC Organic + BFXX Ceramic |
4/5 — firmer, more noticeable bite |
60% regular / 40% sport |
| 3 |
Full FXSS-SC Kevlar® |
3/5 — performance-oriented engagement |
40% regular / 60% performance |
| 4 |
FXSS-SC Kevlar® + BFXX Ceramic |
2/5 — aggressive, reduced low-speed comfort |
20% regular / 80% high performance |
| 5 |
Full BFXX Ceramic |
1/5 — harsh, most aggressive |
100% racing |
The percentages describe PEGA’s intended use balance. They are not horsepower gains, torque-capacity increases or permitted operating-time limits.
Stage 1 — Organic / OEM-style comfort
Full FX4C-SC organic lining prioritizes smooth takeoff and everyday drivability with occasional sport use. This is the comfort-focused choice for customers seeking an OEM-style driving character. Confirm suitability for the vehicle’s actual engine output, especially if tuned.
Stage 2 — Organic and ceramic / sport manual
Combines FX4C-SC organic and BFXX ceramic material. PEGA positions this stage for sport driving and gated manual applications. Expect a firmer engagement character than the comfort-focused Stage 1. Compatibility with an automated clutch system must be checked for the particular application.
Stage 3 — Full Kevlar® / performance
Full FXSS-SC Kevlar® lining is PEGA’s performance-oriented option for applicable F1 and E-Gear systems, with manual applications also offered in the product range. It balances performance use with some regular driving. Correct bedding-in and application-specific clutch calibration are important; it should not be assumed to feel identical to Stage 1.
Stage 4 — Kevlar® and ceramic / high performance
Combines FXSS-SC Kevlar® and BFXX ceramic for a stronger performance emphasis and less priority on low-speed comfort. PEGA lists gated manual and selected F1 performance/track applications. Have the complete vehicle setup reviewed before choosing this stage for an automated manual or modified engine.
Stage 5 — Full ceramic / racing only
Full BFXX ceramic prioritizes racing use over smooth everyday engagement. PEGA describes it as its harshest comfort category and lists racing and selected twin-turbo applications. It is not intended for regular comfort driving. A Stage 5 designation alone does not establish that a clutch will hold every turbocharged engine’s output.
Power output and clutch torque capacity
A clutch transfers engine power; fitting a higher stage does not create additional engine horsepower. HP or kW describes power, while Nm or lb-ft describes torque. Clutch selection must account for the engine’s torque delivery and intended use, not peak horsepower alone.
There is no universal HP or Nm limit stated here for Stages 1–5. Capacity is specific to the complete clutch assembly, including its dimensions, friction surfaces, clamping force, condition and operating temperature. The same lining stage in two different vehicles does not necessarily provide the same capacity.
For a capacity recommendation, provide the vehicle model and year, clutch part number, manual or automated transmission type, engine modifications, measured or expected HP and torque, and street/track use. Identify whether dyno figures are measured at the engine or wheels. Use the rating confirmed for that exact clutch configuration in the product specification or written quotation.
Related PEGA terms and installation information
-
HPC: High Performance Clutch, used in PEGA’s lining terminology.
-
FX4C-SC: PEGA’s organic lining family, used in Stages 1 and 2.
-
FXSS-SC: PEGA’s Kevlar® lining family, used in Stages 3 and 4.
-
BFXX: PEGA’s ceramic-based lining family, used in the Stage 2 and 4 combinations and the full-ceramic Stage 5.
-
Break-in / bedding-in: The initial operating process that establishes contact between the friction surfaces. Follow the instructions supplied for the actual lining and vehicle; there is no single mileage rule given here for all stages.
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Engagement feel: How progressively or abruptly drive takes up. A harsher engagement rating does not automatically mean a heavier clutch pedal.
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PIS / calibration: Applicable automated manual systems require the correct installation and learning procedures. Stage selection does not replace diagnosis, bleeding or calibration.
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Included work: The chosen stage identifies the lining specification. Flywheel work, release bearings, sensors, hydraulic repairs and other services are included only when stated in the listing or approved estimate.
PEGA’s stage and lining guide · About PEGA Clutch · Ask GTE to match a stage to your vehicle
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