How to change Unit System in BeamNG.Drive

Go to the settings and click "User Interface" and choose whatever you want

Metric (SI)

This one is for KM/H

Imperial

This one is for American people

British

This one is for British people

Custom

For custom one you can choose whatever you want.

Length
Temperature
Weight
Volume
Fuel Consumption
Power
Torque
Energy
Pressure
Date Format