i have a 1988 gmc k1500 4x4 5.0 with a th700r4 tranny and i just rebuilt the tranny myself and all new atf. yesterday i installed my tranny and it wont go forwords, it feels like it wants to move but it does not move so if i lift the truck the tranny will move and shift all gears, od,d,2,1 all works and r too but you can hold both wheels with your hands and give some gas and the wheels wont turn it like jerks????? please help i am trying to sell truck thanks

 

First, is the transmission full of fluid?... Did you adjust the TV cable? How long has it been running? One minute? Two minutes?