After finding leak arpund rim of trans pan.  I ordered a gasket.  

I was checking to see if there are any pitfalls or suggestions to getting it right.

I assume drain pan from the drain bolt, then pull the pan and replace.  Will anything drop or fall from the underside of the pan on removal that i should be concerned with.

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Kim, you probably have the pan well sealed. Look a little higher and you will probably find that your leak is from the dipstick tube O'ring seal. This is a common leak source. Clean and dry the area around the tube where it enters the transmission.  The tube must be square and straight to the case opening. After cleaning all oil off, dust some baby powder around the area where the oil is apearing, you'll be able to find the leak when it soaks the powder.

Another leak source is the oil cooler lines. There are two hoses connecting the spigots out of the transmission to the lines running to the radiator. Those sometimes do leak and can look like the pan is leaking when the oil runs down the transmission case.

Your description of the leak comming off the right front corner points more to the dipstick tube as the leak source.  HTH

Hi David,  yep, i already thoufht of that,  seema dry there.

Secondly,  after tapping and measuring for two hours, third gasket split at 10 lbs,    i know it was flat,  it was not warped,   thanfully i didnt load up anoth 35 doallrs of trans oi .  Wits, end,    gonna give it a rest for a day or so.

For reference,  used fel pro gaske .  Its a black oily looking dasket.   Im guessing cork, but has a black look.

Would doubling the gasket with an adhesive help the  pan to seal  a bit better and reduce a good deal of  the labor related to the trans pan change ? 

Who knows if the gaskets that are now available resemble  the stock original gaskets regarding thickness 

i do know that the gasket for the thermostat housing is half what they used to be stock 

I do double that gasket always myself 

just a silly example but could be a good part of the sealing issue you are having 

Hope you get it sealed this time but that would be my next move if the second gasket presents a problem 


The gasket you have will tell the story, if you let it.  You need to take a very good look at it.  
If you split a gasket at 10 ft-lbs, then something isn't even.   Maybe someone hit the flange of the transmission with a scotchbrite wheel or a sander, and rounded it out.  Look at the way the edges of the gasket protrude after it's tightened.  Does it squeeze out only around the bolt holes or is it uniform?

You had a pan that seemed over tightened in the past.  Did you look to see if one of the bolt holes has a tiny crack from overtightening?     If you have a drain plug, drain the pan completely and let the transmission dry overnight, then the following day remove the pan and gasket.  The fluid will remain on the gasket in the exact location of the leak and the sealed portion will be dry.  You can then focus only at that point, looking for the cause.  

Sounds like a plan.  Will give it a go.  Put straitedge on case and see if its flat 


The pan and gasket are supposed to be assembled dry without any sealer etc. If sealer is used, a torn gasket is usually the result. The sealer acts as a lubricant allowing the gasket to be squeezed out as the bolts are tightened. Tighten the bolts in a multi staged criss-cross pattern. HTH

This thread is turn out to be an exceptionally good education on installing a trans pan gasket correctly and of value to many who plan to do this repair at some point in the future 

Very nice repair support going on here !


Sorr of an aside her .  I was buyin tran fluud yesterday, and got the castrol thatvwas gm and before 1983.  Inasked forvthe gallon siz .    She took to counter and chrged me a nickel.  Yes. 5 cents,   apparenetly castrol is reconfiguringvthe label so to dump stock at least atvcarques .   It was 5 cents for a gallon.  Yes a gallon, so if you need fluid,  and thats your brand,  and ur store has it,  id give it a try.    I bought 2,  saved 60.00 on firstvtwo debacles.     Just fyi


This looks like the perfect time to be dealing with what the trans filter needs to be freshened up while you are in there already 

Cleaning or replacing the filter and fresh trans fluid is the way to get this done right for the long haul to protect the trans 


Ok.  Is that a pull then plug back in operation, or more in olved, not sitting near my book.  I can order one if need be,  giving carvwork a day off tomoro



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