Mechanically the car is using, stock chasis, stock frt and rr shock & spring, upgrade micro ball diff set. The wheels do spin freely all four and when throttling also. Is just that my steering, i have to sub trim it to the right until 100 then trim it again another 15 at the front screen of my 3pk, then only the car can go straight. But right after throttlilng the car would go spining or donut. My bl esc is just like the on and off and im using 11.1v 3 cell lipo. Even i have reduced the throttle curve to -100 the max, still it goes donut. I even lock tight my rear ball diff because its just keep spinning . . .