there have been people that have used the 2 speed.i asked about it awile ago and was kinda talked out of it.it seems when you put the 2 speed in you lose the slipper clutch.this makes it very hard on the drive train,especialy if you are jumping.i think i will try it some day.i wish they made stronger diffs and other drive parts for the mt 2.a 2 speed and a bad ***** motor would be alot of fun.