[i4n]

It looks to me as if you didn't have the diff tight enough (which would also account for the lack of acceleration as you were probably only FWD). I did something similar on my XXX-CR when I first got a brushless set-up (melted 3 diffs before I swallowed my pride and asked for help).

I ran my Durga with the standard diff and a Losi 6.5 in it for a few months before upgrading to the 501 diff halves with no problems (only did it to be safe during a rebuild when I also changed to ceramic balls). With the power you get from the 6.5 you want to do the diff up tight to stop it slipping (that's the job of the slipper) but as DCM points out in the other thread, not too tight that you 'crack' the glue holding the diff rings onto the outdrives.

It also looks like one of your belts was set too lose and slipping judging by the marks on the centre pulley (but that may be from where the diff destroyed itself).

I'd give it another go, when you adjust the diff it should be tight, but still smooth to turn when using the wheels when installed in the car. Bed it in by holding one wheel and running at 1/4 throttle for 30 seconds and repeating on the other side and then re-adjust and it should be fine. I also check that they haven't loosened by holding the front set of wheels between my knees and trying to turn both rear wheels in the same direction at the same time and then reversing to try the fronts.

I'm sure one of the other Tamiya guy's will offer some advice in not too long a time... (while I was writing my reply!)