First time for everything, I reckon. Never had this happen before in all the years I have been changing my own and everybody else's fluids.

Trans pan started leaking in right front corner area about a month ago, figured it was time for fluid/filter anyway. Been real busy so I kept checking and adding fluid as needed until I could get around to dropping pan. Changed everything, checked pan rails for strightness, made sure gasket surfaces clean, put it all back together - next morning, more drip. Figured it was the cheap rubber gasket (Wix filter but I used an Advance Auto filter kit rubber gasket).

Tore into it again, this time adding a drain plug to pan, up line pressure a touch while I was in there, dinged bolt holes down, made sure that all mating surfaces were clean, re-checked pan rail for straightness, put cork WIX gasket on this time. Same result - more drip.

Now I am POed significantly. Need to get this stopped because I am off to mountians next week for hunting and don't want to have to deal with adding fluid while up there. Mag-Hytek has been on wish list for a while so this may be an early Christmas present.

Any suggestions on the best gasket to use? I have never had any trouble with cork or rubber so I am at a loss. Why this pan started leaking is a mystery but I want to get it fixed - correctly. I have never used any sealer on trans pan before so question is - are there any sealers that work and stay sealed when subjected to trans fluid?

Any suggestions appreciated.

 

The new style MOPAR ones are great, they are a "plastic" material with raised rubber sealing rings. Very nice.

 

Are you sure it leaking from the gasket. It sounds odd that it would start leaking and 2 new gaskets later it's still leaking.

 

If the pan bolts have ever been over-torqued, as people often do in an effort to stop a leak, the pan can get distorted and will be impossible to seal. Sometimes the distortions can be pounded out, otherwise it's time to step up to an aftermarket oversized pan.

I've heard a lot of folks complain about the old style Mopar cork gaskets leaking.

 

Yeah, the over-torque scenario may be partially responsible (I admit, I did crawl under there and "snug" them down to stem the flow - but they were significantly more loose than I would have expected - thermal cycling maybe) but I wonder why the gasket just started leaking after it had been sealed for the better part of two years.

Seems to do it more cold than hot so I will have to investigate further. Mag-Hytek may be best solution (although not the cheapest).

The pan rails checked out OK with an engineers straight edge so I figured the gasket would fix it. Oh well, just another excuse for tinkering on the truck

Never bent a pan before so maybe I was due.

 

Check the dipstick tube at the base. I changed my pan gasket 4 times before i got smart

 

forgot to mention why, theres a ruber seal that goes on the new ones, the old one doesnt have that, therefore , prone to leaks

 

i had the same problem and i bought a mag hi-tech but that didn't fix it. check the seal on the overdrive unit thats where mine was leaking.

 

Smokefrom4 nailed it - thanks.

Finally got around to crawling back under there now that the semester is over. Wiped everything clean and waited for the weeping to show itself - sure enough - dipstick tube. The o-ring in there was cracking from age and vibration. 15 minutes and one o-ring from the kit I keep in the shop and she doesn't cry anymore.

My record with sealing trans pans remains untarnished.

 

I just used "The Right Stuff" by Permatex. Cheap and works great. Will not harden and is impervious to trans fluids. BUT, is not compatable with rubberized gasket material, but will work with cork.

 

If you desire the extra capacity AT pan and don't want to spend the bucks for a shiny aluminum pan, just go buy an AT pan for the old 727 AT's. There is an article over on dodgeram.org that says they fit perfectly, and they are around $40. I've never tried one though.

 

I would have to question the extra capacity of old stock 727 trans pans (will go read the article when I get a chance). There are 4 727s in the collection of vehicles I maintain for myself and my brothers - the original pans are not as deep as the stock 47RE pan on my CTD by at least an inch (727 is almost flush at back rail where ours hangs down an inch or more).

I have added stamped steel Mopar deep pans to 2 of the 4 727s for extra capacity. The last 727 stamped steel deep pan I bought about 10 years ago was $80. They came with a pickup extender that sets the filter back down in the bottom of the extended pan - without the extender the filter would be about 1.5" above the bottom of the pan and subject to starvation under hard cornering or from extreme angles in rock crawling (both deep pans went on 4WDs, a W200 Dodge and my Scout). Without the extended pickup you would be playing roulette with the trans IMO.

The DC stamped steel deep pan was the only game in town about 10 years ago. Now there are several aftermarket pan manufacturers with top quality products - you just gotta want to pay for them.

 

For my money only cast alum pans will do and there is major diff in pan depth from 727 to 618.