Hi Makin14,
I do not think you can rig a modifier at all. When you exported the mesh with the animations, I think it automatically apply all modifiers. This is probably why the animation in Unreal was weird. For rigging you will need have a bone for every track. If you want I can take a look at it. Also, maybe I can do some of the rigging for you if you want, but idk. I will at least take a look at your mesh, and maybe try importing into Unreal to replicate the problem. Also, is your tank a model of some real life tank?
Gurthang325