Glossary of Auto Terms

DriverSide's Car Dictionary has the most comprehensive definitions of automotive terms. This auto glossary can help you decipher what your mechanic is fixing and what the purpose or function of the particular auto part or accessory is for. We have taken the mystery out of automotive service jargon, so that you don't have to.


Gear Ratio

Gear ratios mathematically determine the relationship between your engine and your transmission. Gear ratios are chosen by manufacturers to provide desired performance characteristics like acceleration and fuel efficiency. These do not change unless the gears themselves are physically replaced, and are not "wear" items.

See Also:
Clutch Pedal
Combustion Chamber
Timing Chain
Schrader valve
Passing Gear

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