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1995 (4EAT) transmission pan issues


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Hi All-

 

I dropped my AT pan a few years ago and reassembled with the paper/cardboard gasket. I got a little too heavy handed on the bolt torque (apparently) and over the years it developed a slow leak. Nothing too major but I could see the gasket splitting by the bolts.

 

Anyway, fast forward to yesterday. I wanted to drain the ATF and decided to fix the leak by dropping the pan and reassembling. Numerous searches on this board plus advice from a former Subie tech friend led me to forget the OEM gasket and just go with Permatex red (hi temp) RTV. This friend also advised that ATF will basically always be dripping off the rear edge of the pan sealing surface (from the nether-regions of the AT i imagine) but you can just wipe it and then quickly stick the pan up and it will be fine.

 

So I gooped the pan pretty good, wiped and stuck. Waited a full 24 hrs to make sure the RTV was cured. I come back today and ATF is leaking off the back edge through the RTV!! Well, that sucks. But wait, there's more - I pull the pan off only to find the RTV still gooey and wet (not cured) pretty much all around! My tube of RTV was pretty old (couple years) but if it was bad, wouldn't it just harden up?

 

Let me sum up my questions:

 

- I know everyone has an opinion, but ... OEM paper gasket or RTV (or anaerobic?) or both??

 

- Luckily I have a lift to work on but should I be blocking up the back end of the car to lower the angle that the transmission sits at to try to centralize where the dripping comes off of the transmission? (so it doesn't run down the back edge). i guess this is irrelevant if I'm just going with the gasket ...

 

- I bought a new gasket from Auto Parts Warehouse a while ago. It's about a mil thick and cardboard like. If I go with gasket, is this good enough? Someone said it's worth it to go with OEM

 

- What is the bolt torque for those pan bolts. I read 42 in-lbs somewhere.

 

I'm leaning towards doing this again with the paper gasket and maybe using some copper gasket spray sticky stuff just for good measure. That way at least it is easy to remove/clean if it leaks again in the future (as opposed to the RTV disaster i currently have).

 

Sorry this was so long. Advice appreciated ...

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Your post isn't long its complete.

 

And its typical. I see these leaking all the time.

 

I recommend:

1. Fuji Bond Red. (dealer or I can ship you a tube-see site below)

or

2. Rubber type gasket.

 

Don't use paper or cork and don't use a sealant that isn't the red mentioned above. anerobic works well sometimes if you want to use that.

 

3.5 foot pounds is spec torque I believe that would be about 42 in pounds.

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I had to pull my pan off, due to noisy pump, the pan was dented and closed off filter screen inlet. I let it sit fro a couple of days dripping. Wiped it good and clean, even up the side wall of the trans. Then I used a rubber gasket that came with the filter screen kit. Applied a supper thin layer of black RTV as gasket cement to hold it in place. Used the low torque mentioned above.

 

6+ months no drips :banana:, now if cam seals would be quite that easy, they would already be done.

 

Greg

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Thanks guys, I think i'll just go get the OEM gasket. Just called the dealer and they described it as "rubber-y".

 

Any advice on how to get a bunch of RTV off of the pan (it finally did cure)!??? Sigh, what a pain. Guess I better get the ole scraper + wire brush + elbow grease out.

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You probably dented the pan around every bolt when you overtorqued it with the cork gasket. That's probably also why the RTV didn't work. Use a ball peen hammer and a block of wood on the backside to flatten each of the dimples around the bolt holes back out.

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I dropped my pan in my 4EAT about 9 months ago, sealed it up with some grey stuff (GD, what was that stuff is used? It was locktite something or other that was anerobic I believe), wiped off the back of the trans, slapped the pan back up there, tightened all my bolts up, waited about 15 min, topped of the trans with atf, and haven't seen a leaked yet. I even drove 3 hours on the freeway to get back home about 20 mins after topping of the atf. Well, I take that back, I didn't tighten down 2 bolts in the back enough appartently, so there was a tiny little bit of atf coming out after 7 months, but I wiped it off, tighten it up, and haven't seen anything since then.

 

So it is doable without the gasket, and I didn't even try to do it "properly" before adding atf. So I would try using some different sealer, take your time, and you should be good... Or get the gasket if it's easy and cheap.

 

Wait... They actually have a gasket for it? What's the part number for that? I looked and didn't find one, so that's why I went with the "RTV" method when dropping my pan. I will need to order one of these up to install my new pan on my rebuilt trans I am getting shortly, so this is good info. That is if the gasket is the better method.

 

Let us know what you end up doing, and how it works out!

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Any advice on how to get a bunch of RTV off of the pan (it finally did cure)!???

If you have a compressor 3m Scotch Brite Roloc discs. They have to be the greatest thing ever for removing gaskets, rust or paint. They turn a half hour job with a razor blade into a two minute job. Before I had one I just used a razor blade very carefully. RTV usually comes off easially with a blade though it's 20 year old gaskets that are a PITA.

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Chrysler makes a really good sealer specifically for ATF/Trans pans. Most all of the dealer parts guys know what it is. Ford also makes a sealer in a caulking tube that is for diesel engine oil pans. It will work with ATF also, but beware if applied correctly you have have to darn near destroy the pan to remove it if you use that stuff:grin: It can really get you out of a jam though if you need to "make" a front oil pan to timing cover seal that won't leak.

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I always have the best luck with Ultra grey when making gaskets out of RTV. The red stuff never works for me for some reason.

 

Anaerobic is not the best choice for a stamped steel pan gasket as there will be different sized gaps between the bolt holes, especially if the pan bolts have been overtorqued. The gap distance may be insufficient to allow the sealer to dry.

Anaerobic is best suited for machined aluminum/steel mating surfaces, where the gap between surfaces is within a few thousands of an inch, and mostly uniform the entire way around.

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  • 2 weeks later...

Thanks for all the advice. Here's an update:

 

I went with the OEM gasket. Part # 31397AA041. It's definitely not rubber, feels more like cardboard but it did seem thicker than the aftermarket one I had bought.

 

To remove the dried RTV I used a pneumatic die grinder with a "fine" wire brush rotary attachment. It worked really well. Scraped off some of the black paint but the surface was still smooth enough. I also spent time hammering out the pushed in bolt holes (91Loyale was right) to make it nice and flat.

 

I used a thin layer of that Permatex "super high tack gasket" stuff on the new gasket, pan-side only. You can let it dry and it just gives is tacky surface. Didn't use any RTV.

 

What was surprising - since the car was up on a lift for 6 days the slow drip from the tranny basically emptied the whole thing! I ended up refilling it with about 7.5 qts of ATF .. or was it 8.5? Anyway, might be an interesting alternative to the "flush" method if you want to change most/all of the fluid ... and you have a week to wait around!

 

I was reaaally gentle on the torque. After a few days of driving I snugged them all up just a touch and no leaks yet.

 

One other tidbit - I was searching this forum for ideas on how to get a good reading from the ATF dipstick. As you probably know, it is difficult. Someone suggested making a cross-hatch pattern on the dipstick using coarse sand paper. This made reading it a lot easier. It's still a challenge to read the hot/thin ATF on there but much better than before.

 

Now on to my leaky oil separator plate! uhh, when I get around to it!

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Glad it worked out! Thanks for the part number as well. I will be ordering up one of these in a couple months, seems like the "cleaner" method for sure.

 

Please post back if you end up having any leaks using the new gasket!

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