Modify Vehicle height in-game.

Hi there,
We are building an off-road racing game, the vehicle has many modifications, such as gears/engine/suspension which we have been able adjust easily. One thing that we must be able to adjust is the vehicle height and this we assumed would require many different chassis that you can swap out with different bone positions, but this crashes the engine when we try to swap it. Anyone know the correct way to modify the vehicle height in game?