• ODT Gun Show & Swap Meet - May 4, 2024! - Click here for info

Any TH350 transmission experts on here?

ok i have been rebuilding automatic trans for 45 years there is no check valve in the pump on a turbo 350 and if all the fluid draind back from the converter it would not be enough to fill case to the top where vent is at you need to if fluid is coming from aka dip stick tube 'detent cable 'speedometer housing o rings or shift rail seal all are easy fix
 
BEEN 25 YEARS SINCE IVE WORKED MUCH ON AUTOMOBILES. USULLY THE FRONT PUMP SEAL GOES BAD AND FRONT PUMP BUSHING WILL WEAR AND THATS WHAT LETS FLUID COME BACK OUT OF TORK CONVERTER. SHOULDNT BE ENOUGH FLUID TO COME OUT OVERFLOW. USULLY THE SEAL ON DIP STICK TUBE OR DETENT CABLE , SHIFTER SHAFT LEVER SEAL, OR SPEED OMETER CABLE O RING GET HARD AS WELL AND THIS IS WHERE THE FLUID LEAKS OUT FROM OR EVEN TAIL SHAFT SEAL WILL HARDEN AND LEAK ! JUST WHAT I REMEMBER OVER THE YEARS .
 
I know there are several seals that can leak but this trans doesn't leak anywhere until it sits for a few days and then it leaks a lot from high up on the case. The dipstick shows overfull then. But when I start it up and shift through the pattern, the dipstick is dry (no fluid showing). I'm assuming that's when the fluid goes back into the torque converter.
Thanks to everybody. I need to find a good shop that knows the old cars.
 
Any fluid coming out of the vent is going to be while running. ( issues with the pump cross bleeding or way over full. )You would have to stand the car straight up to get a gravity leak out of the vent.
Is the trans, pan, dip stick and tube all original?
 
The trans is the same as when I bought the car but I know nothing about the internals. It has a stock dipstick and tube and a aftermarket finned aluminum pan. I'm certain that overfill is not the cause. When it sits for a few days and leaks down, the trans won't go into gear until I add some fluid.
 
Back
Top Bottom