thank, but i brought my rc to my hobby store and turns out it, it had something to do with the rear diff case. most likely just cracked.Brushless, sensorless motors (like come in most all RTR's) tend to shutter a bit when starting and at low speeds. It is worse in some cars than others; most of the Arrma 1/8's are not too bad. Some times I will hear it as the drive line clanks right at start up. Once the truck is moving, there should be no cogging.
[DOUBLEPOST=1464111048][/DOUBLEPOST]Check this out, post 197 -