Car Rig Problem - Car sinks into terrain

Ive been trying to complete the setup for this rigged car for more than 2 days now, everything is fine, the car simulates properly, but when added to the landscape (or any other rigid body) it just sinks half way inside the terrain, the wheels function properly too, but i cant make it run around like any other normal car. any help?

Is your vehicle’s root bone pivot at 0,0,0 ?