See also:

Tire Terminology and Definitions
Air Pressure: The amount of air inside the tire pressing outward on each square inch of the tire. Air pressure is expressed in kPa (kilopascal) or psi (pounds per square inch). Accessory Weight: ...

Speedometer
The speedometer shows the vehicle's speed in either kilometers per hour (km/h) or miles per hour (mph). ...

TTY Users
OnStar has the ability to communicate to the deaf, hard–of–hearing, or speech–impaired customers while in the vehicle. The available dealer–installed TTY system can provide in-vehicle acces ...