Yep, when my t-maxx brand new I thought there was something wrong with it too. But I took it and showed it to the LHS guy and he said it was normal, it's nothing to worry about, and it has to do with the reverse gear. I've heard that if you put a forward-only setup in your t-maxx, it will not jerk/jump like that. Congrats on the new T-Maxx.