I bought a much larger battery pack (5000 mAH) and I'm still having trouble. I think it is either a problem with transmitter setup or a problem with my motor installation (I installed the Impact 3.1 gear ratio and metal tracks). It appears that my right side tracks spin a little faster than the left causing the tank to turn slightly when driving forwards and reverse. Also when I hold the stick to the left the tank turns appropriately (left side stops while right turns), but when I turn to the right it does nothing and that's when the tank sound engine winds down and restarts. Any ideas for troubleshooting?