Have you ever seen this trans. gasket problem?

I am completely stumped on my 727 transmission. I cant get the pan gasket to stop leaking. I have redone it about 8 times now. I have tried rubber and cork gaskets, silicone, permatex #2, and permatex HiTac. I have tried a brand new mopar pan and I am torqueing the bolts correctly with a torque wrench at 150 inch pounds. This last time I used permatex HiTac and a thick cork gasket and let it set for a week. I filled it up and it didnt leak. I ran the car for 15 minutes and the pan now leaks on two sides. I have looked at the flange and cant see any cracks, and it will leak in different places on the gasket depending on further tightening. Any ideas please ??

Maybe the leak is coming from a differnt spot like the selector shaft seal?

If it is from the pan, try the laminated silicone, multi-lip torqe-limiting gasket, mopar part # 2464324AC. They work great

Are you certain it's your transmission pan gasket that's leaking? The "o" ring seal on the transmission tube can be leaking, the seal for the selector shaft can be leaking making you think it's the gasket. Make certain fluid is not migrating down from up above, then collecting along the pan gasket.

Cuda, check these locations on the trans, trans dipstick tube seal, shift control cable,and lets not for get the neutral safety switch seal, Ive used the gasket mentioned and it worked for me good luck

don't know if it's just me, but i only use a 1/4" ratchet & just gently tighten pan bolts. i've never had luck at 150"lbs. seems the gasket smashes out or the pan bends up! just have to keep eye on bolts for staying tight. haven't found a sealer yet that would work and still allow pan removal. how come nobody makes a pan with a thick flange like the front drive trans? then you could use rtv with no gasket! just my 2 cents.

With the motor not running, If you jack up the rear end real high, all the fluid will go to the front of trans and you will be able to see it dipstick or selector shaft seals are leaking, then lift the front up high and you will be able to see if rev band pin or any rear of trans leaks are occuring. also take wire off of nuetral safety switch and see if the brass pins are leaking. I went lately to Mopar dealer and they sell a reuseable rubber coated metal pan gasket for my Dodge duelly with O-Drive for about $11.00

150 lbs.does seem to much.they must be some strong bolts.

I use the reusable Mopar gasket on my 2000 Ram. I like it a lot. Do they have one that fits a 727?

I also thought my pan was leaking until I found out the leak was from above (in the back). Caused me lots of frustration, gaskets and tranny fluid.

I had a mystery leak once.

Any leak above the lowest point will appear to be leaking from that lowest point.
A friend suggested an old trick.

Clean everything with Brake Cleaner and a rag. Especially around the places mentioned previously in this thread. Spray everywhere with some WD40 and blow baby powder on it. I used a blow nozzle set at about 25psi and just blew it out of my hand. You can be creative on this. Once you have a good coating of powder on the case, pan and possible leak points, let it dry for an hour then drive a couple miles and re-inspect.

My oil leak was was dripping from the bell housing and I thought it was a rear seal. It turned out to be the oil pressure sender on top the block. I swear I never saw any trails of oil before, but I certainly did with the powder.

first, make certain that your gasket surfaces are absolutely clean! no old gasket material, no old sealers, etc. also, make sure that the pan gasket surface is straight. no 'dimples' around the bolts, etc.

use the "healing" gasket from pioneer... part# 749029.

use some thin, tacky sealer... copper coat, hylomar, hi-tack, or something like these... to stick the gasket to the pan ONLY. use no other gasket stuff ANYWHERE, and only use a thin coat. you are only trying to hold the gasket on the pan till you get all the bolts started!

run all the bolts in by hand till they are snug and the pan has contacted the trans all the way around.

torque the bolts to 50 inch pounds in a criss-cross pattern.

torque the bolts to 70 inch pounds in a criss-cross pattern.

torque the bolts to 90 inch pounds in a criss-cross pattern. it is important that you do this in 3 stages! dont just wring things down to 90 in-lbs and call it good.

you wont have any leaks from this gasket if you do this. 150 inch-lbs is too much! this will result in distorting the pan, and make subsequent oil changes, filter changes, etc. difficult.

if you STILL have leaks, they wont be from the pan!

I have encountered this same problem before and it turned out to be the pin for the low/reverse lever leaking at the back of the case and running down around the pan edge making it look like the pan was leaking. Look at the rear of your trans below where the tailshaft and rear case come together. You will see a hole with a 1/2 in. Diameter pin in it. This is the low/reverse lever pin. It seals to the case with 1 little o-ring. The only problem is that the tailshaft has to be removed to replace the o-ring. You will also have to drop the pan to push it out of the hole. A quick way to cure this problem is to go to your local Mopar dealer and get some of thier ATF-RTV sealer. This stuff really works. The best sealer I have ever used period. Brakeclean the pin and case, let dry, and smear a little of this sealer over the pin an case and I promise you it will not leak or come off. Also, The new Mopar reinforced rubber backed gasket is the only way to go for the pan gasket.

That was my problem as stated above on my 63 Dodge.

good info on the 90"lbs value!! any body wants to look, on page#21-96 of 1969 service manual oilpan bolt torque is stated at 150"lbs. wonder what MA was thinking??

I have always had to go back and retorque everything after a drive. That has always worked for me. 150 inch lbs done in stages as mentioned above then drive it let it get warm and retorque. Cork Gasket rubber gasket either one works

Thank you guys for the super ideas, I will take all of them into account next weekend when I once again drop the pan and I will have one of those mopar gaskets. The detective work begins. You guys are great. Cudapower

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I have encountered this same problem before and it turned out to be the pin for the low/reverse lever leaking at the back of the case and running down around the pan edge making it look like the pan was leaking. Look at the rear of your trans below where the tailshaft and rear case come together. You will see a hole with a 1/2 in. Diameter pin in it. This is the low/reverse lever pin. It seals to the case with 1 little o-ring. The only problem is that the tailshaft has to be removed to replace the o-ring. You will also have to drop the pan to push it out of the hole. A quick way to cure this problem is to go to your local Mopar dealer and get some of thier ATF-RTV sealer. This stuff really works. The best sealer I have ever used period. Brakeclean the pin and case, let dry, and smear a little of this sealer over the pin an case and I promise you it will not leak or come off. Also, The new Mopar reinforced rubber backed gasket is the only way to go for the pan gasket.

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Yep, I had this problem once too. It took me a while to find it because at the time I never knew that had an o-ring on it.