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Topic Review (Newest First)
09-26-2012 04:24 PM

Originally Posted by Ruthlessmr View Post
is this the same one that had a vibration ?sounds like the pump seal and bushing might be shot
I had the drive shaft made 1 1/4 " longer and that fixed the vibration.

09-26-2012 04:12 PM
Transmission leal

Originally Posted by rusty duck View Post
What is the correct torque on the TH 350 transmission? Mine also leaks just a bit.
Correct torque is between 15-20 lbs.
09-26-2012 02:41 PM
rusty duck Thanks to all you guys.
09-26-2012 05:44 AM
Merkur87 Try to avoid cork gaskets if at all possible. Most are synthetic cork and fluid will bleed through the material itself.

Maybe the problem is not the gasket at all. It could be a torque converter seal leaking, dipstick tube, or cooler line fitting. This can easily be assumed to be a pan gasket leak.
09-26-2012 01:32 AM
SSedan64 X2 on the retighten/retorque. 2-3 times is usually needed. Some Trans pan holes go into the fluid at the bracket mount area & sealant is needed on the threads.
Cork is best for stock Pans with raised bead flange.
Duraprene is also great, they're reusable.
09-25-2012 06:31 PM
Ruthlessmr It might be opinion but i have had great luck with the cork style gaskets
I use a t handle and retighten them when its hot and usually that seals them all
09-25-2012 05:58 PM
Cape Cod Bob
Originally Posted by rusty duck View Post
What is the correct torque on the TH 350 transmission? Mine also leaks just a bit.
Haynes says 10 ft.lbs.
09-25-2012 10:07 AM
rusty duck
transmission leak

thank you for your reply. maybe a couple of drops over several weeks is not enough to worry about. I'll re-torque to 12 lbs and see what happens.
Rusty Duck
09-25-2012 05:05 AM
Irelands child I have a Ford C4 and have gone through the pain. Transmission pan gaskets - cork leaks!!! There are several different kinds of fiber gaskets plus at least one manufacturer that supplies a steel in rubber version Moroso 93102 - Moroso Transmission Pan Gaskets - Overview - and not inexpensive, but they work. Those pan bolts - if they are conventional bolts and washers without an integral washer( flange head * ) - they leak. I'm using them as well as sealing washers** at 12 lb ft of torque. These DO NOT leak. Then there are Lokar dipsticks - the ones with a single 'O' ring can leak a lot. The 'improved' double 'O' ring version will leak less - Lokar uses the wrong diameter 'O' ring, at least for my C4. Lokar will either repair or replace that single ring dipstick for the price of postage one way - they sent me a new one. I'm now using a locking Hughes dipstick which has a GM type seal that does not leak.

* Flange head - McMaster-Carr

** Sealing washers - McMaster-Carr

As far as pans - all pans are not the same - I went through 3 new stamped steel, including a NOS Ford and now have a Trick Flow aluminum version where the bolt holes wont bend out of shape at normal torque tightness - here's one for the TH350 Trick Flow Specialties Automatic Transmission Pans - TH350 Transmission Type - Search Results for transmission pans -

Did the leak stop? No but it went from a pretty good sized puddle in 3-4 weeks to a couple of spots and my guess is that I have a minor seal leak.

Did I say that I went through the pain with the pans????

Dave W

PS: If this fails, there are bigger problems with that transmission - seals, cracks (tailshaft with a TH350 seems to be not uncommon')
09-24-2012 11:20 PM
rusty duck
Transmission Leak

Not the same. Mine just leaves a few drops on the garage floor and I thought I might not be torquing to the correct spec. Just want to know what the correct torque is for the TH 350 tranny pan bolts.
Rusty Duck
09-24-2012 10:30 PM
Ruthlessmr is this the same one that had a vibration ?sounds like the pump seal and bushing might be shot
09-24-2012 09:24 PM
rusty duck
transmission leak

What is the correct torque on the TH 350 transmission? Mine also leaks just a bit.
09-24-2012 08:02 PM
Cape Cod Bob I went thru the same problem/. I also changed to alum pan and provided gasket. I torqued it properly. Do not over tighten. Next common leak is dipstick tube. Be sure you havre the correct tube for the tranny. It will take either an "O" ring or the top hat plastic type. Be sure your dipstick tube is supported and be sure it is in the correct position. This can be a tuff one to find as the kick down cable is near the dipstick hole and it can leak also.
The speedometer hookup is another culprit and on mine I finally figured out that the brand new driven gear was letting fluid past it. You can get a new bullet to with a new "O" ring for it.
And lastly on my tranny filling it to the full mark was to much fluid. I let it run a little lower and it is better.
All these places leaked on mine after a rebuild. I would go for a cruise and come back and crawl under and look to see where the leak was.
Plus of course I had to wipe everything off . , . Finally got them all.
09-24-2012 02:04 PM
prostreet6t9 Check the manual lever seal and the accumulator.... Both are common leaks and when they do it can look like a pan leaking.
09-24-2012 09:06 AM
454 Rattler I thought you would get more answers than this.

These transmissions have a habit of leaking if they sit unused for a while.

I would suggest that you wipe it off and take it for a short ride, then re-check to see if it's the gasket or some place else.

Good Luck !

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