I had a bunch of new diffs explode on me is why I'm not crazy about them. And I still don't understand the tranny problems. Maybe its just because I keep my trucks light but I have yet to break any gear in the tranny. I twisted a lightweight output shaft(I was shocked) in two pieces and break 3905 driveshafts every time I run but my trannies have never failed. My V-Twin with the spool in rear and heavy weight oil up front gets bookoos of traction(too much) and still hasn't broken a tranny gear after hours of use and straight up abuse. Watch my videos to see that my truck goes through. Maybe I'm just lucky. I do take my trannies apart about once a month just to check teeth and grease them but I just don't have failures. My biggest upgrade suggestion is to get rid of the crazy weak stock driveshafts and then upgrade at least the rear diff.