I had my 4l80e trans rebuilt becuase the truck would barely move in reverse and because it would not shift out of first. Well I put my rebuilt trans back in and reverse is fine now but the trans still will not shift out of first. Does anyone have suggestions on what to check or look at? I know...

2000 Chevrolet Tahoe LT 325,000 miles 5.3L V8, NP8 Transfer Case New 4WD selector switch New transfer case motor (and I have a used one) So, I’ve tried just about everything. I bought this truck thinking it just needed a transfer case motor. I bought the motor, shifted it into 4Hi, and it...