[primetime54]

Searched all TH350 leak threads but can't find one quite like mine. Just wanted to get some opinions on what you thought.

I have a leak from front of tranny which I first thought was a pan gasket leak and of course it wasn't that simple. It does not leak when its running only when it sits and normally soon after shut off and not very much. Probably leaves like a quarter size leak each time. I finally saw where it was coming from last night and I spotted it coming from the front side of transmission near converter but on transmission but can't see exactly see where on the front side the leak is coming from. My first thought was overfill since when I check fluid at cold it was already at the hot mark on dipstick. When I check fluid at operating temp after running through all the gears the level is just above the cold mark so this would make me think it might be low. I'm wondering if it is leak back from the converter at shut off and overfilling.

Just wanted some suggestions from you guys. Also transmission is running fine and shifting smooth. Sorry if this has been covered before but I did try and search beforehand. Let me know if you need anymore info.

thanks
Shea

[1badLemans]

Sounds like a typical front seal leak. This seal goes on the input shaft/pump and has to be hammered on(lightly) with a big socket or maybe some exhuast pipe. The pain is that the torque converter has to be removed so if its in the car, the trans has to be lowered in order to get to it. The good news is that they are very cheap. Good luck.

[Crosley]

hve you looked at the shifter linkage shaft seal?

[primetime54]

Thanks 1badLemans that is something I was wondering about and dreading cause i didn't want to pull tranny but I will be much happier with no leak


Crosley, I'm going to put it up on stands this weekend to take a closer look and if I still can't pinpoint it I'm going to take it some where to put it on a lift. I will let you guys know what I find. Thanks for the suggestions so I can pinpoint my focus.

[scholman]

primetime54,

I am thinking that either the kick-down "O"ring or the filler tube "O" ring.
When I have replaced front seals on these transmissions they would leak under pressure not when it is not running. And the torque converter would be all wet and very noticeable. JMO though.

Scholman
Retired

[primetime54]

thanks Scholman. Yeah the converter is bone dry. its only wet on the front face of the transmission. there is no fluid anywhere else on that transmission except where it leaks down near the pan and makes it look like a pan gasket leak. I have never been an auto guy and I'm beginning to see why Hopefully this will be simple

[scholman]

Primetime54,

I do not know what this transmission is in but I have pulled them back away from the engine out in the rough and rugged hills.
Pull the drive line and put a paper cup over the end so it doesn't leak. I use duct-tape to hold it in place.
Put a jack under the transmission and remove the transmission crossmember. Lower the transmission BUT put another jack under the pan of the engine so you can hold the engine and transmission at this downward angle.
Disconnect the shifter, kick-down cable, vacuum modulator hose.
Remove the bottom two bellhousing bolts and replace them with 12 inch long allthread with a double nut at the end so you can thread them into the block.
Remove the remaining bolts around the bellhousing and disconnect the torque converter bolts. Push the converter back against the transmission then pull the transmission back it will be hanging by the two all thread bolts but you can then pull the converter off of the transmission and see where the leak is. I use a plastic hammer to install the new seal.
You might check the pump cover bolts too. They have seals on them and they leak too. Reinstall the converter making sure it goes all the way back into the pump drive before bolting the transmission back to the engine.
To put it back together just push the transmission back into place, install all bellhousing bolts first checking that the torque converter is free to spin and then install the torque converter bolts.

It is tricky but it can be done.

Scholman
Retired

[primetime54]

Originally Posted by scholman

Primetime54,

I do not know what this transmission is in but I have pulled them back away from the engine out in the rough and rugged hills.
Pull the drive line and put a paper cup over the end so it doesn't leak. I use duct-tape to hold it in place.
Put a jack under the transmission and remove the transmission crossmember. Lower the transmission BUT put another jack under the pan of the engine so you can hold the engine and transmission at this downward angle.
Disconnect the shifter, kick-down cable, vacuum modulator hose.
Remove the bottom two bellhousing bolts and replace them with 12 inch long allthread with a double nut at the end so you can thread them into the block.
Remove the remaining bolts around the bellhousing and disconnect the torque converter bolts. Push the converter back against the transmission then pull the transmission back it will be hanging by the two all thread bolts but you can then pull the converter off of the transmission and see where the leak is. I use a plastic hammer to install the new seal.
You might check the pump cover bolts too. They have seals on them and they leak too. Reinstall the converter making sure it goes all the way back into the pump drive before bolting the transmission back to the engine.
To put it back together just push the transmission back into place, install all bellhousing bolts first checking that the torque converter is free to spin and then install the torque converter bolts.

It is tricky but it can be done.

Scholman
Retired

Thank You