Ha, don't have an answer but the problem sounds really familiar! I have an A-518 that is doing the same thing. Its like the shift lever is in 2d gear (engine brakes same) but no 3d at all. Its in the shop right now. I also installed a shift kit (MOPAR Performance). Started out with no reverse, ball in wrong place (but installed per instructions). Removed ball and now 1 and 2 great but no 3....
