[Solved] Why the wheels disappears? (and other trouble)

Transfer - Dropbox I did make a tutorial made by wishforge and my wheels disappearing: Does anybody knows why?

because your car is not your first body.
under your joint connection:
car = first body, wheels = second body.

Thank you, I will try this soon as possible.

This does not work, it causes strange happens.

no clue what you did. i changed the car to be the first body and everything worked exactly as it should. did you change the joints for both wheels?

here, see for your self:

What I does not understand were the to joints on one object body. I think I will start the complete tutorial again.

Now it works thank you!