Wheels

Upon importing, you will notice that the vehicle has only one wheel. This is because the game instances (re-uses) wheel_lf for all other wheels.

Wheel meshes do not have vertex groups but are instead rigged by a Child Of Constraint (as explained in Drawables > Rigging).

Wheel mesh rigging

Also, wheel meshes have the Is Wheel Mesh property ticked under Object Properties > Sollumz.

Object Properties > Sollumz

That's all that's needed for setting up wheel meshes!

Previewing the Other Wheels

In Sollumz Tools > Fragment > Create Fragment Objects is a tool called Generate Wheel Instances. This tool will create instances of the wheel, allowing you to better preview what it looks like in-game. This is useful when positioning the wheel bones.

Sollumz Tools > Fragment > Create Fragment Objects