Automobile pedal

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"Gas pedal" redirects here. For the Sage the Gemini song, see Gas Pedal.
Hanging pedals in a Subaru Legacy. From left to right: foot rest, clutch, brake, gas.
Standing pedals in a Saab Sonett (clutch, brake, throttle)

An automobile or other road vehicle may have two to four pedals. The arrangement is the same for both right- and left-hand traffic. From left to right:

  • normally operated by the left foot:
  • normally operated by the right foot:
    • brake pedal, which is sometimes wide and elevated above the car floor
    • throttle (known as the "accelerator" or "gas pedal"), controls fuel and air supply to the engine. It is usually narrow and close to the floor allowing the driver's heel to rest on the floor. It has a fail-safe design in that it automatically returns to the idle position when not depressed by the driver.

Pedals can be either "hanging" from the firewall (bulkhead) or "standing" on the floor; the latter is usually used in trucks and buses.

Since the right foot is normally used (for the accelerator or brake) there is no foot rest on the right, not even in cars with cruise control. The left foot only has to operate the clutch intermittently (or has no function in an automatic vehicle) so sometimes a foot rest is provided to the left of the pedals. Some vehicles have a parking brake pedal instead of a hand brake lever; in that case, it is operated by the left foot while applying the brakes with the right foot. Some drivers practice left-foot braking, however it has proved to be difficult to train the left foot to skilfully press the brake pedal thus bringing the vehicle to a smooth stop; instead the outcome is usually a sudden stop.

Many vehicles now include pedals with electric adjustment, a modern iteration of a manual adjustment system available sporadically since the 1950s.

Other vehicles[edit]

Heavy vehicles on caterpillar tracks such as bulldozers or tanks may have two brake pedals; for the left and right side tracks respectively. These vehicles do not have a clutch pedal but two manually operated levers; the clutches and brakes are used for differential steering.

In a bulldozer the gas pedal operates in an opposite way to an automobile; depressed pedal = idle, released pedal = full open throttle.

A twin engined wheel tractor-scraper has two gas pedals next to each other; one for the front engine and one for the rear engine.

Some rail vehicles use automobile-style pedals to control the speed, usually in conjunction with a dead man's switch; this layout is mainly used in trams or light rail vehicles, such as the Z-class Melbourne tram and the PCC streetcar.

See also[edit]