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.
A gear in an automatic transmission that allows the passing of a slower moving car more easily. It is activated when the gas pedal is sharply depressed.