my aluminum center shaft wobbles more than my stock steel shaft. I think its just so long that even the slightest bit of bend throws it out of whack. This might sound stupid, but I was wondering if the long hollow aluminum shaft for the traxxas 4x4 slash could be modified to work. Just a thought. I havent measured anything to see if its even close in length. Not sure what traxxas is doing but the center shaft in the 4x4 slash runs perfectly true.