How to prevent model drifting?

edit

Hey!

I am trying to simulate a model of an ev (like the polaris ranger) using ackermann steering. I currently have a functional simulation that moves around and responds to messages as required. Unfortunately I recently realized that one of the people I am working with set the weight to 50kg instead of the more realistic 500kg which makes it a lot more likely to tip over when going around corners at speed.

However...when I bump the weight to 500kg, everything goes out the window. The model bucks a little bit when it spawns and then proceeds to slide around despite the wheels being still.

Does anybody know a solution to prevent this from occurring?

Thanks!