Splines can be heavy, a frame by frame animation done in 3dsmax could do a better job. Like you can make a separate rig in 3dsmax using constraint and get animation by rotating torsion bar arms. Then bake animation just for the wheel bones.
The reason for that is that animation graph in UE4 is pretty fast if you used build in nodes. Getting a point on a spline is bit more time consuming and would had to be done in code. Even a lookup table could work faster if you want to solve this in code.