904 leaking

[davek]

1970 charger ,installed a wix tran filter and its leaking on the whole driver side of the pan. The wix filter had a rubber gasket for pan. I installed dry. 12 FP torque on bolts and checked them again. Many people said install dry. Should I use a sealer or double up on the pan gasket or get a cork gasket? Any thoughts? Dave

 

[DeltaV]

Check the shifter shaft seal for leaking first.

 

[WileERobby]

Back when we did trans fluid/filter changes, I always used my ol' reliable on the pan gaskets.

 

[Plumcrazy]

Chrysler at one time made a steel rubber coated reusable pan gasket. Probably still available.
That is the gasket you want to use. While you are changing it make sure the pan mating surface is still flat.

 

[1 Wild R/T]

1970 charger ,installed a wix tran filter and its leaking on the whole driver side of the pan. The wix filter had a rubber gasket for pan. I installed dry. 12 FP torque on bolts and checked them again. Many people said install dry. Should I use a sealer or double up on the pan gasket or get a cork gasket? Any thoughts? Dave

Prior to replacing the pan gasket did it leak? If so look elsewhere, shift shaft seal, band anchor pin & dip stick tube... If it was dry before use the OE Mopar gasket mentioned above
Pt # 02464324AD

 

[PlymCrazy]

Like the guys said here Dave, check the side penetration seals for leaking first before dropping the pan again. Spray the housing down with some brake cleaner (or similar) and verify where the leak is coming from.

Only after that’s confirmed to be leak free, drop the pan and verify it’s flat and hasn’t been over torqued or pried on too bad in the past. Also be sure all old gasket material has been removed with a scraper. I typically do a final clean with a cup brush on the end of a drill motor. Should be smooth to the touch running your finger around it.

If you have a good gasket, you shouldn’t need any RTV. But if you do use the RTV (with a gasket) be prepared for some extra work getting the pan off and cleaned up next time.

 

[Charles Cook]

Dave Dave Dave, what have you tore up now??????? You’re a painter not a mechanic. I thought you were tearing up the brake booster. One thing at a time buddy. Lol. You mentioned the drivers side was leaking. Check up above the pan, new trans. fluid can be hard to detect where it’s coming from. Good luck. I’ve never used RTV on transmission covers.

 

[DeltaV]

Check the other stuff first as noted above by our fellow members.

Back to the pan:
When necessary, I use a gasket remover containing methyl chloride. Read and heed the precautionary statements. Then, I wipe down the sealing surfaces with brake cleaner using a clean, cotton cloth; not a paper towel. Wait for the solvent to dry/evaporate and dry install a cork gasket. I finger torque all bolts and follow-up torque them down lightly with a socket, skipping every other bolt; and requiring several passes. Maybe I should use a torque wrench on these trans pan bolts, but I do not.

 

[1 Wild R/T]

Check the other , I use a gasket remover containing methyl chloride.

Where can you get anything containing Methyl chloride these days... Just like most things that actually work it can't be found anymore... Certainly not here in California....

 

[1KoolBee]

Chrysler at one time made a steel rubber coated reusable pan gasket. Probably still available.
That is the gasket you want to use. While you are changing it make sure the pan mating surface is still flat.

Mopar part #

04295875AD​

Reusable Gasket is for a 47RE trans from an 2001 ish ram 2500. 47RE is nothing more than a 727 with overdrive, lockup converter, and electronic governor. 47RE pan is deeper, has a plug, and fits the 727 too. When I sold my 01 diesel it had 220k on it with the original gasket. Probably had pan off 5-6 times, never leaked a drop.

 

[DeltaV]

Where can you get anything containing Methyl chloride these days... Just like most things that actually work it can't be found anymore... Certainly not here in California....

Somewhere in my garage
sitting next to the chlordane & DDT.

I guess he'll have to go with today's formulation/concoctions like CRC 05021 or Loctite SF 7200 (for example)

 

[Plumcrazy]

Mopar part #

04295875AD​

Reusable Gasket is for a 47RE trans from an 2001 ish ram 2500. 47RE is nothing more than a 727 with overdrive, lockup converter, and electronic governor. 47RE pan is deeper, has a plug, and fits the 727 too. When I sold my 01 diesel it had 220k on it with the original gasket. Probably had pan off 5-6 times, never leaked a drop.

Is that the part number for the 904 pan gasket ?

 

[1KoolBee]

Doh! maybe 52118779AB or 4295875?Not sure . They’re Disco’ed anyway. Maybe fleabay?

 

[toolmanmike]

I don't think this has been mentioned buy you need to straighten the gasket surface of the pan out before installing a new gasket. Did you flatten out the bolt holes? I

 

[toolmanmike]

I replaced my 904 pan with a HD extra capacity pan from a late model overdrive.It has a drain plug as well. No leaks.

 

[davek]

I don't think this has been mentioned buy you need to straighten the gasket surface of the pan out before installing a new gasket. Did you flatten out the bolt holes? I

thanks Mike,I did not check it for being straight so I think that was my problem. Hoping and it did leak the owner said. And its clear its the driver side of pan.

 

[davek]

I replaced my 904 pan with a HD extra capacity pan from a late model overdrive.It has a drain plug as well. No leaks. View attachment 1515765

Yep was looking at that today,like the drain plug.

 

[71_SSP]

Yep was looking at that today,like the drain plug.

A month or so ago, I installed the RT Off Road $60 deeper pan from Summit, that is in the link above. I didn't use the rubber gasket that came with the kit. I spent the extra money on the newer gasket, that is also listed above. Its steel/rubber and reusable. It worked great on my 904. Now, 400 miles and a month or so later, still NO leaks! The Summit kit is worth the money, IMO.