Seriously at my wits end

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1BadDodge71

1BadDodge71

FABO Rice Hater
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I posted awhile back that I kept having problems with my transmission pan leaking and thought I fixed it.I took the advice of many people by buying the reusable gasket for the 727 from Chrysler and I even got a brand new oil pan.I threw in a bottle of UV dye to mix with the new fluid and I made absolutely sure I didn't over tighten the bolts.After making sure I topped it off,I took it for a drive and came back to check it and so far so good.So just to make sure,I placed a piece of cardboard under the car beneath the transmission in case it did leak,I would spot it.The next day,I came out and sure enough,there were spots on the cardboard.:banghead:
So,I crawled under the car with my UV light,and shined it on every possible spot where it could be leaking.The speedometer,the shifter lever,safety neutral swith,dipstick tube,and sure enough,the outer edge of the pan was wet and glowed green when I shined the UV light at it.
I'm seriously sick of this and even though it's not a huge leak it still bothers me.I'm at the point where I'm ready to just goop some ATV Transmission Sealant on it. :banghead::banghead:
If anyone has any ideas let me know.
 
New steel pan? Or cast alum? I like a paper gasket with cast pan. Light coat black rvt on both sides and torque wtench to tighten. Look for gouges in both surfaces. Or over tightened pan bolts bulging the pan rail on gasket side. Good luck man
 
Is it the factory pan? I used to have an old dodge ram that had a constant issue with that as well. My factory pan was bent in some areas and would not seal with the reusable gaskets. So I ended up just getting a generic gasket and gooped ultra black on it, then I installed the pan slightly tight and let it set for a few hours.
I tightened the pan bolts to specs afterwards.
Had very little problems after that.
 
I had a similar problem with my 727 a few years ago.

Turned out that The o-ring on the low/reverse piston pivot pin was broken and leaking.

The pin is inserted into the transmission case while The tail shaft is removed.

Requires a lot of tear down to replace it.

You may be able to seal it with some silicone from the outside as a temporary fix.

From underneath the car, look up just above the pan rail. It's the rail that is closer to the rear of the car. To the right of center (closer to the passenger side) you will see the end of the piston pivot pin. It's about a 1/2" diameter pin, but partiall blocked by the flange on the tail shaft. The tailshaft is what is preventing the pin from sliding out.
Clean the area and apply some silicone to see if that stops the leak.

During a rebuild, you would slide the pin out and replace the o-ring.
 
My money is on the shifter pivot lever seal!! Took me 5 years, and countless pan/gaskets to fix that!!!
 
I've seen dipstick tube O-rings leak and look like the pan gasket too....
 
I had the same problem with one until I used a rubber gasket with a thin layer of ATF specific RTV sealer on both sides of the gasket. No more drippage.
 
The product to use on transmission pans is "Right Stuff" by Permatex. Forget the gasket, it really works. I got mine at NAPA.
 
I have seen where the bolt holes in the pan were pulled up from overtightening which makes the surace not flat anymore and caused leakage.
 
jdsduster said:
its the shifter lever seal or the dip stick o ring.
Click to expand...

X2

I use a cork gasket and spray the gasket with the copper spray. Snug it up leave sit for awhile, go back over with a torque wrench, no special gasket, no gasket slipping and never have an issue.
 
I am wondering, have you verified that the leak is actually from the pan/gasket? I hate to see you chase a leak that may be from somewhere else. Its a common problem for the shifter seal to leak and run down to the top of the pan then drip from a couple of different places making it appear to be the pan/gasket? I would make sure that the seal area is washed out along with the pan/gasket. Then start the car and with a mirror watch to see if the shafter seal may be leaking. also check at the speedometer gear o-ring and rear yoke seal and dipstick tube seal. You may have to drive around the block then look again. Dont go to far at one time because once it starts to leak it will run to other areas and be hard to figure out where its coming from. It can be aggrevating but once you find the actual leak it should be curable!
Be patient but make sure you are chasing the real problem.
Best of Luck
Rod
 
rod7515 said:
I am wondering, have you verified that the leak is actually from the pan/gasket? I hate to see you chase a leak that may be from somewhere else. Its a common problem for the shifter seal to leak and run down to the top of the pan then drip from a couple of different places making it appear to be the pan/gasket? I would make sure that the seal area is washed out along with the pan/gasket. Then start the car and with a mirror watch to see if the shafter seal may be leaking. also check at the speedometer gear o-ring and rear yoke seal and dipstick tube seal. You may have to drive around the block then look again. Dont go to far at one time because once it starts to leak it will run to other areas and be hard to figure out where its coming from. It can be aggrevating but once you find the actual leak it should be curable!
Be patient but make sure you are chasing the real problem.
Best of Luck
Rod
Click to expand...
The transmission is rebuilt.I looked everywhere on the transmission for leaks with the black light and very positive it's the pan.This is the dipstick tube I have on it right now and it is very sealed http://www.summitracing.com/parts/aaf-all69120/overview/ (I bought that one because it's nearly impossible to find an original tube and everyone that has one wants an arm and leg for one)I checked at yoke seal ,even took off the driveshaft and no leaks there.I dont see any cracks on the housing and the surface were the pan meets is smooth,straight with no gouges.I may just take the advice of using RTV made for transmissions and a paper gasket and just seal the living hell out of it.
 
younggun2.0 said:
New steel pan? Or cast alum? I like a paper gasket with cast pan. Light coat black rvt on both sides and torque wtench to tighten. Look for gouges in both surfaces. Or over tightened pan bolts bulging the pan rail on gasket side. Good luck man
Click to expand...

Steel pan
This is the pan I bought since it came with the filter.But I used the reusable gasket I already had,not the gasket that came with the pan.
http://www.manciniracing.com/ma727chdepan.html
 
Im sure I didn't over tighten it.In fact it could actually be tightened a little bit more if anyone has any torque specs they could throw at me.I tightened it just maybe a couple of ratchet turns beyond hand tight so It's too tight,but not loose either.The surfaces I always make sure they are straight ,smooth,and clean.
 
Get longer wits so you have more patience.... :banghead:
 
The problem with the dye is, unless the fluid "piles up", you may not pick the dye up with the light. In other words, if the fluid is on a flat surface, like the transmission case above the rail......say coming from the dipstick tube or shift shaft seal, you will have a difficult time spotting it, because it is spread more thin than if it is in drips on the pan.

Have you gotten a mirror and looked all along the top of the pan rail at the dipstick tube and shift shaft seal areas? At this point, I would leave no stone unturned. It's obviously leakin somewhere.
 
Whatever you do don't use silicone! We use a non drying product from perfect seal called #4. Much better suited for problem areas. I like silicone gaskets but sometimes Victor tuff cork gaskets work better with an old style pan.
 
I have never in my life of workin on cars (since 1974) used any form of sealer ever on a transmission pan. Always been able to get them to seal as long as there wasn't a crack or pinhole somewhere. It's just not something I have ever recommended.

Not that that amounts to a hill of beans.
 
I had the same problem. It turned out that the seal around the neutral switch was leaking and it looked like the tranny pan was doing it.

I added an additional O-ring and some liquid gasket on the threads (or pipe dope, I don't remember)
 
1BadDodge71 said:
Im sure I didn't over tighten it.In fact it could actually be tightened a little bit more if anyone has any torque specs they could throw at me.I tightened it just maybe a couple of ratchet turns beyond hand tight so It's too tight,but not loose either.The surfaces I always make sure they are straight ,smooth,and clean.
Click to expand...

Trans leaks can be a PITA, get some Desenex foot spray powder. Clean the areas that are wet as best you can, and spray that powder around the pan, and around ANY area it could leak. Let it dry, then fire it up and take it for a short spin, then look for the leak.
 
RustyRatRod said:
The problem with the dye is, unless the fluid "piles up", you may not pick the dye up with the light. In other words, if the fluid is on a flat surface, like the transmission case above the rail......say coming from the dipstick tube or shift shaft seal, you will have a difficult time spotting it, because it is spread more thin than if it is in drips on the pan.

Have you gotten a mirror and looked all along the top of the pan rail at the dipstick tube and shift shaft seal areas? At this point, I would leave no stone unturned. It's obviously leakin somewhere.
Click to expand...

Exactly.

I'll tell you guys what works pretty well for finding a leak.
Clean the trans up and spray it with aluminum spray paint, drive it and have a look at it again.
The fluid will leave a VERY visible track in the paint where it migrates.

Sorry, but I have to laugh a little at the "Wits end" part over a trans leak. :D
 
RustyRatRod said:
I have never in my life of workin on cars (since 1974) used any form of sealer ever on a transmission pan. Always been able to get them to seal as long as there wasn't a crack or pinhole somewhere. It's just not something I have ever recommended.
Click to expand...

^^^ Xs2

If you have 2 clean and true mating surfaces, let the gasket do its job. Adhesive can be used to hold a gskt in place, but not as a sealer. And I just shake my head at using rtv on both sides of any pan gskt., that just helps the gskt "squirt" out imho. my .02

cheers
 
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