See also:

Reporting safety defects (US only)
If you believe that your vehicle has a defect which could cause a crash or could cause injury or death, you should immediately inform the National Highway Traffic Safety Administration (NHTSA) ...

Speedometer
The speedometer 1 indicates vehicle speed in miles per hour (MPH) and kilometers per hour (km/h). ...

Using the brakes
Avoid resting your foot on the brake pedal while driving. This will overheat the brakes, wear out the brake pads faster, and reduce gas mileage. To help reduce brake wear and to prevent the bra ...