hey guys me again.. so i rebuild this 4l80e for a buddy nothing crazy just a stock 3500 dump truck. did a full rebuild bushings, clutchs, steels, pistons, seals etc. i dual fed the unit since its for a dump truck gonna haul trailers and be loaded. everything went right clutch clearances forward and direct about .050 5 clutch bw frictions. i vaccum tested the valve body everything held decent so i ran it.. btw trans wasn’t that bad before the rebuild just was due hard lip seals and clutchs were slipping forsure. installed back in the truck once i got fluid level right i went to pull it out the shop and engaged reverse fine like normal. once i put it in drive it felt like it was in 3rd or 4th gear really heavy… checked for codes no codes. checked if the speed sensors were reading they were. i tried manually putting in 1st nothing the same deal HEAVY. i put it manually in 2nd and it felt better a bit. so i put the pressure gauge and i was getting around 40psi in park 60psi in reverse and around the same in every other gear. i unplugged the transmission and checked pressures like that and was around 180psi in park 200-210 ish reverse and around the same in drive which looked good to me. once i would it in boom back to 40psi low pressures.
ive build 80es before and never had this issue. i’ve been looking around if anyone had this issue and can’t seem to find anything. any input will help thanks.

 

found the issue… so after taking the trans down again put it back on the bench and took it all apart to find what i did wrong. everything looked new just the way i put it together checked the valve body everything vacuumed tested good but noticed the afl would get stuck a bit moving it in n out. so i took apart a trans i had there already had the afl reamed every thing tested good everything looked good i put it all back together and back in the truck and the SAME thing… after that i knew it had to be a wiring issue. so i plug in my hp cable and i command 1st gear and same thing was heavy barley moving i commanded 2nd and it would feel a bit better. then i commanded 3rd and boom truck took off fine like in 1st gear so then i commanded 1st gear while moving and it shifted up so i knew from there wiring issue. i dropped the pan and looked at my atsg book and i had both shift solenoid connectors flipped due too the new rostra shift solenoids that are a “updated” so you can interchange them both and they have both connector types. was my fault 100% for just connecting them like a moron not checking but man i do not like that new design. just wanted to put it out there maybe it can happen to someone else.