Reddog9,

It is a Bezier Circle. I just renamed it 'path' to simplify things at the time. Sorry for that little confusion.

 I've studied the other artist's file a lot. The lattice objects that the tracks are parented to only have keyframes on the "Y axis" so he's not moving it on the Z axis as we thought. This is the main thing that's throwing me off. That and the fact that the wheels (and their lattices) are rotating on the same axis perfectly without any axis being locked.