It would be very nice of you to upload such a project, thank you ! I understand that the suspension bones have nothing to do with the blur problem. I only tried to reproduce the Copy Bone setup on the left part. If you could also upload your 3d file it to see the rigging it would also help a lot. For my vehcile I followed this tutorial to properly rig my mesh : How to Rig and Setup a Custom Vehicle in Unreal Engine 4 - YouTube