Andrew gotow car

Whay I can´t use the andrew gotow car script in other car model?
I made all slep by slep and don´t func
anybody can help me plss

The first error points to
EngineRPM = (FrontLeftWheel.rpm + FrontRightWheel.rpm)/2 * GearRatio[CurrentGear];

Did you setup up gear ratio values in the Inspector?

I thik no
how can i do this?

In your first image, on the right (Inspector) is “Gear Ratio”
Click that and enter the 5 numbers from the tutorial.

Yes now is func
thancks