diff problem

You only have front wheel drive right now.Your REAR diff cup is shot.

what is the rear differental cup? is that the part that connects to the drive shaft?

hah never mind i found it ...the little hex head that your rim locks into is spun out so i need new hexs and then 2 new rims lol

The cup is what holds the planetary and sun gears of the differential. It is inside of the diff housing (the part that you can actually see). It is common that the steel crosspins in the diff break out of the grooves they reside in inside the cup. When this happens you will lose power transfer to the applicable wheels. The plastic part is what you more than likely need to replace.

http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXSP75&P=7

If you hold the rear bumper and give it throttle and the rear tires do not spin as much as the front, you have a problem in the diff or the drive shaft.

I've merged your threads. Only one thread per topic, please.
I've also moved it from the 'Reviews' forum to the Tmaxx forum.