This is the note I sent Redcat:

Got the new complete diffs <font color="#c00000">part #BS803-025</font><font color="#666666"> </font><font color="#000000">Installed them and had to shim front and rear with2 thin shims each.tried 3 each and could feel it binding more then I would like. put back together took time to equally tighten the top of each case down (like a torque pattern on a cylinder head ora wheel). Checked for play both tight very little or no bind at all. Ran at 1/2 throttle 10 min constant, some turns, no full punches just very light driving. Sounded good. That night took apart and inspected shaft play and....... </font><div><font color="#000000">"it was back" so I shimed each 1 thin shim <font color="#0000bf">(shims are same size as shim that was installed from factory.)</font> Nice and tight very little or no bind. so each diff has 4 thin shims on each shaft. </font></div><div><font color="#000000">Installed and will test today. </font></div><div></div><div></div><div><font color="#000000"> My question is what if I run today and end up needing to re-shim again???? I have run out of shims., Also all this is making me scared to really run this thing and punch it. I have the Hobbywing program box and it was suggested that I take out some punch so the gears will last.I did not buy this to make it less fun to drive or slower so it will last. And I certainly don't think all of the You-tube Vids with Ali-shanmo bashing this thing hurt sales (that is what made me get this!!!) But I have yet to do half of what he did on those vids!!!!......Was he not stating he was replacing diffs on the Earthquake 8e in the vids? On taking the punch out, I have not heard anyone doing this yet and still being able to get the front wheels to lift or wheelie, which by the way is soooo cool..............</font></div><div></div><div><font color="#000000"> So What is next? Sorry for the long note I am just getting really frustrated.....I am beginning to feel like one of the customers I talk to at my Chevrolet Dealership when their vehicle is here for the same repair time and time again because the manufacture hasn't a developed a fix yet and they are almost out of warranty. On a much smaller scale I am in the same boat.</font></div>