Trans. pan gasket

I need to put a new trans. pan gasket on a 727 and was wondering what gasket is recommended these days. It's been probably 20 years since I last changed a trans. gasket and at that time I tried one of the Mopar rigid, reusable gaskets and it leaked quite a bit so I think I'd rather try a conventional cork or rubber type gasket. Recommendations?

The only reason that gasket leaks is because the pan is not flat. Or a crack in the flange of the case.

Lay the pan on a very flat surface. You will probably see some or all of the bolt holes bell mouthed. Flatten them out.
You should not be able to get a feeler gauge of more than .013” (if memory is correct) between the flange and surface.
Don’t use any sealers, just clean the trans and pan with thinner and bolt it together.

You can’t over torque this gasket, you will just strip threads.

These new style oil pan and tranny pan gaskets are heavily embossed with sealing ribs. This seems to seal well against the machined surfaces of the block and tranny cases. But do not do a good job sealing against the stamped steel pans that have their own stiffening ribs. I use those gaskets with Hylomar on the pan side of the gaskets with good success. Non hardening Permatex would probably also do a good job there.

Can’t speak about all stamped pans but the ones from Chrysler conform to the PIP seals and their contour.
I’m thinking if you check a 62 727 pan against a 2007 48RE the beads are probably identical.

I ran the silicone/metal gasket on the pan of my 64 300's 727, no leaks, but I did end up heli-coiling all the pan bolt holes because most of them were stripped due to incompetent "mechanics" and I just did them all while I was there.

I neglected to mention I will be replacing the factory pan with a deep cast aluminum pan. The last time I used the Mopar hard gasket that I mentioned in my original post that leaked was on my 71 Road Runner that had the factory steel pan on it. So maybe this time I will have better luck. Still tempted to use some sort of sealant though as I hate having leaky oil and trans. pans.

Clean both surfaces and put it on dry.

You will be happy with the results.

The new gaskets Mppar hard gaskets with the O Rings on a Summit or B&M aluminum pan with no sealer of any kind works.

Forgot to mention, this gasket used longer bolts in production due to it being thicker.
Be careful using the standard bolts.

Like Transman pointed out, the newer gasket needs a different bolt. Its like 2 threads longer. Not much but enough to strip out holes in the case if they are not used. The dealer can hook you up with those. Same goes on the 904 and its derivatives.

Other than the Mopar hard gasket, are there any others that anyone would recommend?

Given that you have two machined surfaces, it doesn't get much better than the style gasket being discussed here. At least, in my opinion.

I am old school. I use cork or if I have to use it I use rubber with great results.

1. Make sure pan flange is flat. Often mechanics think tighten it more and it'll fix it and the dimple the pan at the bolt holes causing more leaks.

2. Add a little trans fliud to the pan and use it to coat the gasket. This will cause the gasket to swell a little and prevent it from sticking to the metal making removal less of a mess.

3. Install the pan snugging the bolts a little bit. I use a 1/4" ratchet to prevent going overboard. Repeat the bolt snugging process around the pan repeatedly until the gasket starts to squeeze out or the bolts stop getting snug. Every pass the pan around will cause the first bolts to be loose by the time you get to the last ones. You are done when they stop getting snug.

I pretty much never have pan leaks. Can't get that darn seal on top of the shift lever to not leak when the torque convertor drains back into the trans case but the pan doesn't leak.

I will say that I do like the newer style trans gaskets that are rigid and reusable but since a cork gasket comes with the filter I use them and save my money. Only a couple bucks but I am cheap.

A&A transmission sells a cork gasket on a steel frame. I have had great luck with them.

Just got a valve body from turbo action came with a cork/rubber gasket. what the heck if its good for turbo action should be good for me, went to service manual torque specs 150 inch pounds, tighten up gasket split around most bolt holes and pushed out pan rails.

Most manual shafts have a ton of play. This solves it: https://superiortransmission.com/product/superior-k071/

I've got this Moroso 93110 gasket between my 727 and the deep MP aluminum pan.

Love it...steel core, with rubber around it!

Look at the ad a little closer - it says not to be used with standard steel pans.

Wonder why.