I have a 2003 GMC Yukon 5.3 4l60e. Just rebuilt Engine..transmission and transfer case. It wants to go forward in R.N.D..all of them. The best way i can describe it is like it has a trans brake. Everything new in trans. New neutral safety switch. cable is good. Not my first 4l60e rebuild. I have done a few but this has me stumped. No codes. Any help is greatly appreciated.