How to translate car wheels to suspension?

Hey guys,

I am trying to update the tires y-pos according to the suspension, like when the car flies the suspension is fully stretched and the tires should also move to the specific y-position.

There is something about a wheelhit that handles all the stuff but I dont get the correct query syntax of it.

 function TranslateWheels(){
     wheelFL.GetGroundHit(wheelhitFL);
     var p = new Vector3(wheelhitFL.point.x, wheelhitFL.point.y + 0.33f, wheelhitFL.point.z);
     tireFL.position = p;
 }

This will let the tire be always at the point no matter if the wheelcollider is not touching the ground.

Any ideas?