Wheels without an engine. Question without an answer..

I am building different truck rigs and everything works fine with my wheel colliders until I add another rig to my truck, throw on some wheels, and hinge that rig(a rigidbody) to my main Truck cab i.e,- A Semi-rig.
Has anyone figured this out in practice, or in theory?
Hinge joint kinda works but the second rig’s wheels do funky things. And the weight of the rigidbody messes up the Main Truck’s driveability, even at minute Mass amounts.
I’ve tried every conceivable setup I know, well prob not every but maybe an extra brain can help.

cheers.

I’m having a similar problem. Trying to move a wagon towed by a cart and restricting the movement only to a horizontal plane. For instance the cart has physics (wheelcolliders) but the wagon not, I’m trying to make lateral move by scripting.

Does anyone have a suggestion?