Originally Posted by monkeyracing

With the stock dogbones, or often with the TA03 ball diff and CVD axles, there's enough play for the axle to slip out of the outdrive cup, or the outdrive cup to slip out of the diff. Either way, you lose drive on that side.

The solution is to insert a 3mm o-ring into the outdrive cup to take up the slack. Tamiya has also suggested taking those red foam shock cap inserts, cutting them in half and using them the same way. O-rings are just easier.