I know this probably sounds like a simple fix but I can't get my tranny pan on my 93 F-150 to seal. I've replaced the gasket 3 times over the past two years and still leaks. I bought a new pan last week that came with a cork gasket. This time is was my fault b/c i filled it with fluid before torquing it. Stupid. Anyways, bought a rubber gasket and still leaks, only from one or two bolts though. Anyone have an opinion on rubber or cork gaskets? Im almost to the point where I want to just RTV the heck out of the pan without a gasket and hope it works. Anyone have any thoughts? This thing is driving me crazy b/c it is a little more than just a "small leak". Thanks in advance guys.

 

A late model pan is smooth on the rim, and it uses a reusable rubber pan gasket.

Or you can grind off the the raised area around the bolt holes and just use silicon.

 

Yeah the new pan is an aftermarket pan and is smooth all around. You think RTV would do the trick? And if I do use RTV, I should not use any gasket at all right?

 

My experience with several of my personal vehicles is that rubber and cork don't work too well. Don't know why, they used to be just fine years ago. I blame the Chinese.

I like the "composite" material. Kind of looks like black fiber board or thick paper. The composite does not "squeeze out". Cork will split or squeeze and the rubbers will squeeze out.

I also do not torque to spec. I have found too many times that torquing the pan to spec causes the gasket to squeeze out somewhere and leak. I torque til they are snug and watch all around the pan for the gasket to NOT squeeze out. WIld ballpark is the torque is maybe 1/2 to 2/3s of spec. Use an inch pound wrench.

Also I like to use some sealer on the pan and the mating area of the tranny. I like the black Permatex stuff and sometimes Copper Seal a gasket. Be carefull not to let any sealer get loose on the inside of the pan, wipe off all excess from the inside edge of the pan and tranny.

Follow directions for the sealer. But, in general I like to clean the surfaces really well with something like brake cleaner on a clean rag, and then let the sealer sit for awhile so it skins over really well. I even like to "glue" the gasket to the pan and let it sit over night before sealing the tranny.

If you use sealer, usually you cannot resuse the gasket and next time you have to scrape it off. But I got tired of leaks so I use sealer.

You might put in a drain plug so that fluid changes don't always require a dropped pan.

Good Luck,

Jim Henderson

 

Jim,
Thanks for the reply! Best help so far. I think I'm going to have to try the sealer. I have some copper sealant on hand so... As for the composite gasket, any idea where I could pick one up at? I had previously installed a drain plug on my stock pan and it made draining fluid a breeze but my new pan came with a plug already installed. Ill see what I can do next week and try to repost with results.

If anyone else has any advice it would be appreciated.
Thanks again.

 

I would just silicone the pan, I know that works for me I have done it many times on many makes and models of transmissions. I just did it today on a Jeep Cherokee. Its the best way to keep it from leaking. That flat pan rail and with a drain plug is ideal for silicone. Just do it right, keep it clean and dry and dont use to much. Lay a bead about the size of a 1/4 drill bit, go around the bolt holes to the inside(or all the way around). Hand start all bolts before tightening.

I have not used rtv but I wouldn't be scared too use it in a pinch.


If you must have a neoprene gasket I would try to buy one from a transmission repair shop.

When I use a gasket and I want that extra protection aganset leaks I use this on both sides of the gasket.




Found at NAPA