I would suggest going even lower with the harshness settings to smooth out the road FX effects.Try going as low as 0.0 or 0.1 to see if that helps. If not, is it possible that your FEI setting is too high on your wheel's driver? As for the wheel clipping and smoothness issues, can you elaborate a bit more there? Is it due to the wheel wanting to center too strongly, too much wheel resistance, etc.? Yep, in the file there is a (strengthen_low) setting. Increase the value to tighten up the wheel center.