Topic: Suggestions to install C6 trans pan so it won't leak?

[Angela]

After years of searching for a non-dented original C6 pan, I took advice from this forum and bought a Blue-dot "concours-correct" C6 pan for my '67.

Next step is to remove my existing pan, replace the filter and install the new pan.

I bought a new pan gasket and the instructions state to install the gasket dry (i.e. no sealer). Doing so is contrary to what I'm accustomed to seeing in these applications. So, I'm looking for feedback as to what other folks have done.

I've had tremendously good luck with Permatex "Right Stuff" gasket maker, which is specifically made to adhere to and survive within gas/oil environments. Should I:

(a) Install the pan with a gasket dry - no sealer
(b) use Permatex "Right Stuff" between pan and transmission -no gasket
(c) use a thin film of Permatex "Right Stuff" between the gasket and pan, as well as between gasket and transmission?
(d) Other method?

Thanks!

[carlite65]

an old time ford mechanic taught me to install the pan by using 3M weatherstrip glue. glue the gasket to the pan, let it cure a bit then install to trans-no glue there. i have been doing it this way for years with good results. just my .02 here.

[1967 eight barrel]

Carlite is correct. You can also use 3M spray adhesive. You don't want any adhesive on the transmission side, being scraping aluminum clean can be an issue. I do the same with oil pans. 3M 77 adhesive on one side of the gasket surface, then I mask the rail of the pan from underneath the lip, spray it. Wait for it to tack up, line up the holes and press it down. It also cleans off with lacquer thinner when you service it next time.

                                                                                                                  -Keith

[Bob Gaines]

After years of searching for a non-dented original C6 pan, I took advice from this forum and bought a Blue-dot "concours-correct" C6 pan for my '67.

Next step is to remove my existing pan, replace the filter and install the new pan.

I bought a new pan gasket and the instructions state to install the gasket dry (i.e. no sealer). Doing so is contrary to what I'm accustomed to seeing in these applications. So, I'm looking for feedback as to what other folks have done.

I've had tremendously good luck with Permatex "Right Stuff" gasket maker, which is specifically made to adhere to and survive within gas/oil environments. Should I:

(a) Install the pan with a gasket dry - no sealer
(b) use Permatex "Right Stuff" between pan and transmission -no gasket
(c) use a thin film of Permatex "Right Stuff" between the gasket and pan, as well as between gasket and transmission?
(d) Other method?

Thanks!

You didn't mention what type of gasket material you were going to use. The factory used cork and that is the type I have always had the best luck with . Others may have a different opinion.

[67gtasanjose]

... You can also use 3M spray adhesive. You don't want any adhesive on the transmission side, being scraping aluminum clean can be an issue... 3M 77 adhesive on one side of the gasket surface, then I mask the rail of the pan from underneath the lip, spray it. Wait for it to tack up, line up the holes and press it down. It also cleans off with lacquer thinner when you service it next time.

                                                                                                                  -Keith

As good of an idea as Carlite65's ...only a bit neater and less likely to squeeze out and be seen. (not Concours if you see the yellow stuff) I've used the yellow adhesive too MANY times and it works good as suggested but would caution to use sparingly if you choose that product so it matches the factory look best.

... The factory used cork and that is the type I have always had the best luck with . Others may have a different opinion.

+1, Factory ALWAYS used CORK.

CHEAP Cork will split easily and squeeze down when tightened too much as an effort to stop a leak.
As already suggested, A QUALITY CORK GASKET is best and glued to ONLY THE PAN SIDE and I'll add that a person might use the sealant as described on the new gasket and new pan and flip the pan (& gasket) over and apply pressure on a clean, flat surface (maybe a stack of phone books?) while taking the other pan down. This should help to evenly press the adhesive between the pan (with gasket stuck to it) while the adhesive dries.

[carlite65]

used sparingly and used the black. after pan has been installed wipe edges with lacquer thinner so no visible sealer shows.

[1967 eight barrel]

I like cork too. It expands a little bit with the fluid and tends to seal itself, just don't over-tighten them or they split. The issue I don't like with weather strip adhesive is the removal if need be.
                                                                                                           -Keith

[carlite65]

3M makes an adhesive remover specifically for that.

[Angela]

Thanks for the help guys. Reading the feedback, I'm confused, however. I'm seeing some say to use CORK gaskets, glued to the pan. I think, however, Charles is stating he's used the BLACK gasket material, or maybe he meant he's using cork with black sealer? Can someone clarify which gasket is best to use? I suppose cork is the method of choice because it would match factory usage.

I bought the pan and gasket from NPD, and the gasket they supplied is black rubber.... not cork. I can certainly go find a cork gasket, but I must admit I've never had much luck with cork.... they always seem to split and fall apart on me.

Also, I did a bit of searching and discovered that "Duraprene" Pan Gaskets appear to be a brown-in-color coated cork gasket used by many transmission shops.... supposedly the coating keeps the cork from tearing apart yet retains the cork composition. From the side it should look just like the factory cork gasket. Anyone have experience with Duraprene gaskets?

[67gtasanjose]

Thanks for the help guys. Reading the feedback, I'm confused, however. I'm seeing some say to use CORK gaskets, glued to the pan. I think, however, Charles is stating he's used the BLACK gasket material, or maybe he meant he's using cork with black sealer? Can someone clarify which gasket is best to use? I suppose cork is the method of choice because it would match factory usage.

I bought the pan and gasket from NPD, and the gasket they supplied is black rubber.... not cork. I can certainly go find a cork gasket, but I must admit I've never had much luck with cork.... they always seem to split and fall apart on me.

Also, I did a bit of searching and discovered that "Duraprene" Pan Gaskets appear to be a brown-in-color coated cork gasket used by many transmission shops.... supposedly the coating keeps the cork from tearing apart yet retains the cork composition. From the side it should look just like the factory cork gasket. Anyone have experience with Duraprene gaskets?

Only reason cork splits is because of lack of understanding (or it was a cheap, offshore cork product) Trans shops DO USE quality, cost-effective parts but they have a huge advantage over the majority of Do-it-Yourselfers...Experience! The transmission shop cannot afford a leak that burns up their work so some things are not worth saving a buck or two on.

That being said, use what you find comfort or acceptance over with your selection. Over-tightening the pan has 95% of the time caused the pan to be damaged and in turn will split a good gasket (regardless what material) so it is good you are starting with a new pan. Tighten evenly and slowly TO SPECS and do not follow any temptation to tighten further! If you did it correctly, there will be no leak. (even if you used NO SEALER at all!...though the trans case and pan must be 100% oil-free if you go without any sealer at all, not an option really once you've had any fluid in the tranny)

[Azdriver]

I am going to be trying a Lubelocker on my trans pan. I recently used one on the 9" center section with great results. I realize the black material of the lube locker is not correct and not cork but no leak would be my first priority.

[rockhouse66]

There are certainly different quality levels of cork, but the C6 in my old CJ Torino always leaked and I realized it was actually soaking through the cork seal.  I replaced it with a rubber seal to fix it.

[mtinkham]

.......(maybe a stack of phone books?) while taking the other pan down. This should help to evenly press the adhesive between the pan (with gasket stuck to it) while the adhesive dries.

What are phone books.....just kidding....trying to be young again!

[KK2558GO]

I have rebuilt over over 10,000 transmissions in my shop over 30 year span and never used any type of sealant on pan gaskets.  I curse when I have to clean off someone else's  stuck pan gasket material when doing a "reseal or rebuild".  Hey, the factory never used any!  Ok, now I feel better.

[67gtasanjose]

I have rebuilt over over 10,000 transmissions in my shop over 30 year span and never used any type of sealant on pan gaskets.  I curse when I have to clean off someone else's  stuck pan gasket material when doing a "reseal or rebuild".  Hey, the factory never used any!  Ok, now I feel better.

lol! I understand your pain! Welcome to the site, glad you found a good topic that strikes "home" for you to chime in on

I also work on cars for a living and have encountered many-a do-it-yourselfer jobs that really "get to me".

I attempt to say this with all due respect but as you already know from being a professional, your parts store pan gasket is usually balled up in some sort of disfigured shape and almost impossible to lay out on a pan to lift it up while laying on your back in the driveway so the only realistic way is to "glue" it at times (to JUST the pan).

I know that in the Trans Kits bought by Rebuilders, this "balled up gasket" situation isn't true PLUS the transmission is on a fixture & OUT of a car making things much easier for the rebuilder. The outlines "suggestions" are more for the home-hobyists, trying to make things a little easier which can produce a little less stress when it isn't "STILL LEAKING AGAIN!!!!???" lol!