thuan: I don't understad why the other code doesn't go, but if it is okey now: Nice! [Smile]

ventilator: Yes, the same code I have, too... Perhabs the models are the problem, but I have used a cube for the car and symple cylinders for the wheels for testing it: same result [Frown]
I think there was a change between the actually A6 Physics Engine and the Beta Physics Engine - and because I have to use the Beta Physics Engine, yet - I have a car, which jumps around the room... could this be right [Wink] ?