tc4 ball diff help needed

[phildogg]

Hey need some help here a friend of mine just got a tc4 and went BL with it it has a spool in fr. and the ball diff in rear. it seems to send all the power to the front (spins tires) so we brought it in and tightened the rear diff but still no good,any ideas. I'm looking to get one also and hoping we get all the bugs worked out of his before I try on-road w/BL. thanks for the time.
phil