I recently bought a 2wd stampede and bought a brand new Velineon System (3500 motor / 3s ESC) and put it in with no issues. Only ran it 2-3 times this winter and never heated the motor much at all.
I soon decided to get a Stampede 4x4 roller and swap everything into that truck. So I now have it all together and the motor seems to have some bad low speed cogging. Also, there seems to be "dead spots" in the motor where if I can slowly go from 0% to 100% throttle and the motor will never even move. I can hear it twitch when I first move the throttle, but if it doesn't move at first, it won't move at all. If it's stuck like this, you can either roll it a little by hand, or repeatedly pin the throttle and it will move just fine. If it's rolling, there is no issues at all. Also, it doesn't seem to do this as often in reverse.
I never had this problem with the 2wd. I'm currently running trenchers all around and 13/54 gearing... the rest is stock. I don't expect the gearing would be the problem? Any ideas??