The transmission is making whining noises, slips just before shifting 2/3, reverse is fine. Fluid is not discolored or bad. Went through tranny completely 20,000 miles ago. Put all new electronics and valve body in. Some kind of pressure not correct maybe? Any help is appreciated. Bounces back and forth between shifting into overdrive or not to also. Lock up was gone long ago.

 

If you aren't getting lock-up, it's like that the trans has overheated, and burnt itself up. The ATF +4 won't necessarily show anything, or even smell different..... may want to drop the pan, see what ya got. While you are in there, could try adjusting the bands, and see if that improves anything.