- place a SUV or a truck anywhere on the map
- get in
- press your forward key a very short time, just enought to let the game detect it, but not long enought to actually move
- the vehicle will pitch left and right very quickly
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those steps allow you to see the issue, but the vehicle is shaking even if you actually drive it.
==================== EDIT :
It visible if you spawn one of these vehicles in the Virtual Garage.