I recently rebuilt my 4r70w. Completely took it apart. New gaskets, bearings, steals and clothes. All hard parts were in great shape. Took apart cleaned pump. Cleaned and reassembled. New torque converter. Filled with close to 6 quarts merc.v . Disassembled valve body and cleaned everything reassembled with new gaskets. I did not replace any solenoids. All new fluid In trans. 7quarts, converter 6 quarts, t case 3 quarts.... The problem I'm having is the truck revs really high and won't go,for about 30 seconds, off and on the gas. Once it's moving it shifts really good 2nd,3rd o.d. no problem... Come to a stop. Doesn't hardly move. Once it finally does, it shifts and goes fine. Another problem is when going up a steep hill, if you get on it and it down shifts, it hits really hard, tire chirping hard. Reverse is perfect Every thing is fresh. I took my time with this and just can't figure what it could be... Bad (new) torque converter ? Valve body stuck? Solenoid bad. Some body please help... Fluid level is perfect. Bright red color. No noises. On the road at speed with moderate hill it shifts perfect.. just won't go from a stop. 2000 ford f150 4x4 4.6 4r70 w

 

When you cleaned the low one way clutch, is it possible you installed the part containing the rollers and springs backwards? That could be what you missed.