Are you using loctite on the screws going into the motor? I don't think that's a good idea. I may be wrong, but I'd hate to risk any of that stuff seeping down into the bearings.

I don't remember if you mentioned it, but what battery config are you running? I'm running an 8XL, which has a KV rating similar to that of the 2.5d, on 5S and it is nuts. I'm talking uncontrollable at full throttle, geared 12/46 with MT tires. I'm almost thinking that I should go with an even higher turn motor, maybe a 1500kv.