Mmmm this is a new one to me. I built mine as the manual suggested and got someone at my local club to check them and they've been fine ever since. Were you at Oople?? I spoke to a few 502 owners and wondered if I spoke to you lol.... I can honestly say I've never had any problems with my diff on the 502, you're sure your slippers not too tight?? That's what sounds like is making your car wheely....
Scotty....
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