自動車用語 G[Back to Top]

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Gas filled shock absorberA shock absorber containing a charge of low pressure gas that helps keep the hydraulic fluid from foaming.


Gov-lock differentialA locking type rear differential that uses centrifugal force to move a counter-weight and lock the rear wheel together under wheel slip conditions. Widely used in trucks, by General Motors, starting around 1973.

(see also limited slip and posi-traction)
Gray marketA vehicle or part imported through other than the official distribution network.

Such vehicles may not meet safety, emission or lighting standards of the country into which they are imported.


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Head gasketMaterial used to seal, coolant, oil and compression in the area where the cylinder head(s) attach to the engine block.


Hot tankA metal tank, filled with a heated caustic solution and used to clean cast iron and other ferrous materials.

The hot tank is effective at removing grease, dirt and some rust.

It is not appropriate for aluminum or soft metals and will cause damage to them. For this and for environmental reasons, the use of hot tubs has diminished greatly in recent years.


(see also jet wash)
HSLAAn acronym meaning high strength low allow, referring to a type of steel used in automobile construction.
HSSAn acronym meaning high strength steel, referring to a type of steel used in automobile construction.


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Included angleThe angle formed by a combination of camber and steering axis inclination (SAI).

(see also camber and SAI)
Independent repair shopAn organization designed to service vehicles and owned independently, as opposed to a franchise or mass-merchandiser.


Injector flushThe practice of cleaning fuel injectors with a chemical and some sort of pressurized device.

Often sold as necessary or as maintenance but only beneficial when there is an actual problem.


(see also wallet flushes)
Inner tie rodThe flexible pivot that connects the steering mechanism to the outer tie rod, usually by a threaded connection.



Steering-box type systems usually use a tie rod similar to the outer connecting each with a threaded sleeve.


Rack and pinion systems normally use a rod as below.


Threaded to the rack on one end and with threads to provide adjustment and attachment to the outer tie rod on the other end.

(see also outer tie rod and rack and pinion)
IPCAn acronym meaning Instrument Panel Cluster. The computer that operates the dash instruments and often the security system and overall communications between computers on the system.



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JalopyA slang term for an old vehicle, particularly one in disrepair
Jet washA cabinet fitted with high pressure nozzles and a rotating floor, used to clean automotive components.


Hot soapy water is blasted against the components as they rotate inside the cabinet.

The jet wash is very effective for cleaning aluminum, iron and plastic components.


The cleaning solution may be recycled, is non-toxic, and the jet wash is considered environmentally friendlier than other cleaning methods.


(see also hot tank)
JounceDownward travel of the suspension; pushing the vehicle down in the front or rear to settle the suspension, as in alignment.


(see also rebound)
Jounce bumperFlexible devices, often rubber, located at points on the suspension where contact might otherwise occur between components that move on jounce and rebound.


Flexible cushions that slip over the shaft of McPherson struts and dampen bottoming.


(see also jounce and rebound)
Jump timingA malfunction where a timing chain, belt or sprocket breaks or slips and the camshaft is no longer properly synchronized with the crankshaft.


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KAMAn acronym meaning Keep Alive Memory. Battery powered backup memory used by the various control modules on a vehicle.


Keyless entry systemSystems designed to unlock vehicles without the use of a key. Often a remote transmitter with a push button, but numeric key pads have also been employed.


Very often linked to the onboard security system and can be used to activate personalize radio and seat position settings as well.



KilledWhen an engine unexpectedly quits running and the ignition is still on.


(i.e., The engine killed)
KinkA type or degree of bend in a frame resulting in a fold of metal with a radius of 3MM or less.

Generally accepted as the point at which a frame can no longer be structurally repaired.


KOEOAn acronym meaning Key On Engine Off.


One state in which pre-OBDII vehicles could be tested. (see also OBDII and KOER)
KOERAn acronym meaning Key On Engine Run.

One state in which pre-OBDII vehicles could be tested.


(see also OBDII and KOEO)
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Labor knockA rattling, pinging type noise, normally experienced on acceleration and under load.


Left unattended engine damage can result. For more information see our Detailed Auto Topics Valve clatter, spark knock, pinging and pre-ignition. (see also spark knock, detonation and pinging)


LeanA condition where the amount air to fuel is more than the ideal 14.7 to 1. Too much air or too little fuel in the ratio.



Can result in loss of power, high cylinder head temperature and misfires.
LeaseA method of purchasing a vehicle, where equity in the vehicle is traded for a lower monthly payment.


A lease is similar to rental, except the person leasing is general committed to the term and conditions of the lease.
Please see our Detailed Topic,Problems With Automobile Leasing for additional information.


Limited slipA type of differential that attempts to apply equal force to both drive axles.

This is usually accomplished by linking them together through a series of clutches and drive plates that only slip when necessary.


(see Posi-traction)
Lock-up (torque converter)A clutch in the torque converter that “locks” the input to the output at a specified time.

This prevents further slippage of the torque converter and improves fuel mileage. Lock-up clutches are normally controlled by the computer through solenoids and hydraulic pressure.


(see also Torque converter)
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M/S tireStands for mud and snow, a tire that can be used in mud and snow as well as on the highway.


MaintenanceService performed and parts replaced in the hope of preventing other, more expensive parts from failing.


For instance coolant is replaced in the hope of preventing corrosion damage to radiators, heater cores and engines.


The cost of the coolant is a fraction of the cost of the repairs it can prevent.

Read more on maintenance.


McPherson strutA suspension component that contains a shock absorber but also supports the weight of the vehicle through a spring or torsion bar.

See also shock absorber
Menu pricingA method of assigning a price to a specific service decided on in advance. A name is assigned to the service with no regard to whether it is needed or will address a problem. Menu prices are often set at a level geared to get the client in the shop and never intended as what will be charged.


(see also spiking the job, brake job and tune up) and how much is a brake job and how much is a transmission.
MerconA brand name for a type of automatic transmission fluid, widely used by Ford Motor Company.


The name is also used, with a suffix, for several other specialty automatic transmission fluids, such as Mercon Premium, Mercon LV, Mercon V, etc.


(see also Mercon V, Mercon SP, Dexron and ATF)
Mercon SPA brand name for a type of specialized synthetic automatic transmission fluid, with additional additives, and used by Ford Motor Company in certain transmissions.


Mercon SP may not be replaced with Mercon V, which would not meet the same specifications.

(see also Mercon V, Dexron and ATF)
Mercon VA brand name for a type of synthetic automatic transmission fluid, with special additives and widely used by Ford Motor Company.


Mercon V may not be replaced with Mercon, which would not meet the same specifications.

(see also Mercon, Dexron and ATF)
Metal on metalThe characteristic grinding noise made when the friction material wears off of brake shoes or pads and the metal backing scores the rotor or drum surface.


MILAn acronym meaning Malfunction Indicator Light.


An indicator to the driver that a fault has occurred in the computer management system See our section on Engine Diagnostics.

(see also Check Engine Light)
Multi viscosityIn oil, the ability to change the resistance to flow over a range of temperatures.


For example 5W30 is the SAE designation for an oil that can flow like a five-weight oil at low temperature (0 degrees Celsius) and like a thirty-weight oil at high temperature (100 degrees Celsius.)

(see also viscosity)