Suggestions on a new "chrome" tran oil pan leaking

Biggredd2069

Biggredd2069

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On my 68 Chrysler Newport with 727 transmission the old transmission oil pan was warped and leaking. I didn't know it warped at the time so I tried just putting a new gasket on it and a new filter. That was a waste. Bought a new chrome transmission pan and new gasket. Still leaking. What should I do next? I'm not made of money. Should I take it off and sand it or something to get any chrome off and retry? Or just bite the bullet and get a non chrome steel pan. And I still gotta new gasket and more fluid again.

Thanks
 
How are you installing it? Are you putting a light coating of gasket seal/maker on each side? Are you torquing the bolts with a torque wrench? Uneven torquing is my First guess.
 
I did not use gasket seal. Should I try that and keep this pan? I would assume I need a new gasket? I did use a torque wrench and made damn certain I didn't over torque. Was scared of warping a new one.
 
Are you sure it is the pan seal leaking? There was a thread a bit back about another seal on a 727 right above the pan (lockdown lever maybe) leaking and it looking like a pan seal leak.
 
I can't remember if they offer a reusable gasket for these trans or not, but yeah, I would go get a good quality gasket and some gasket maker. I run a light film coat on each side and follow the instructions on the tube (most have to sit and dry for a period of time) and torque it in a crossing pattern to spec. Remember, these don't need to be very tight as that will squeeze the gasket out and/or strip the threads. I'm thinking it's like 15 ft/lbs
 
I just had the transmission pulled the day after I swapped this pan and had the rest of the seals replaced professionally. I then took it to a different shop and had the carb rebuilt, per the other thread going on right now, and they called me yesterday saying my pan is leaking. They were actively looking for other leaks for me to fix. (I need a new steering gear box and valve cover gasket to finish the other leaks after this tran pan).
 
As previously noted, the 727 transmissions often leaked from the gear shift input lever, check that first. If you are sure the gasket on the pan is leaking, try re-torquing it first, these gaskets had a tendency to compress some as the oil warmed up in the transmission. If that does not solve the problem, remove the pan and be sure to remove all traces of the old gasket. The mating surface of the pan and the transmission should be cleaned to remove all traces of oil as gasket sealer will not adhere to oil. Then reinstall with fresh sealant and a new gasket.

Dave
 
I too have the same issue, and sure enough there is a leak from the lever that goes into the transmission above the pan. What is this part called? Is it a relatively easy fix? Thanks
 
Well it's snowing today and cold. I'll try just giving a flofol up tightening on the next couple days and see if that stops out. Otherwise plan b
 
If you decide to buy the seal replacement tool, get the number off of the ChiCom seal it comes with and buy a quality National or other US made seal. Saves having to do the job again 6 months down the road.

Dave
 
Fill tube Oring is famous for drooling usually because it gets replaced with a regular rounded edge style ring when it is actually supposed to have a flat edge.

As for the chrome pan, verify that the flange is flat by setting it flange first on a flat surface. Then grind the chrome off the flange surface, use a quality gasket and as added insurance, a thin as in almost see through it application of your favorite RTV silicone.

Kevin
 
Davea Lux said:
If you decide to buy the seal replacement tool, get the number off of the ChiCom seal it comes with and buy a quality National or other US made seal. Saves having to do the job again 6 months down the road.

Dave
Click to expand...

Personal experience on this Dave?:rolleyes:
 
A trick I used to use for new or persistent transmission leaks was to not use any sealer(ever) and use a 1" flat punch and tap the edge of the pan around the circumference to seal it up.

also to never over torque the bolts using a high quality 1" pound torque wrench

I was warned to never use any sealer(especially silicone gasket maker) on a transmission gasket as it would cause it to squirt out or the glue would get into the trans & clog it up internally at one point or another.
 
Biggredd2069 said:
I need a new steering gear box and valve cover gasket to finish the other leaks after this tran pan
Click to expand...
The steering box (if leaking) maybe splashing back into the pan and making it look like it is leaking. Especially if you're using trans fluid in the power steering pump.
 
Davea Lux said:
Unfortunately, yes. The ChiCom seal got hard, thru chunks and leaked. Think the rubber was the wrong compound.

Dave
Click to expand...

Not that this helps much but i recall commando1 posting a few years back about some HQ transmission pan gaskets that are or were available... @commando1
 
You're not paying close attention Biggredd2069.. JTC haz given you the perfect fix. REAL GASKET OF TENNESSEE. WHEN YOU GET YOUR PAN RAIL FLAT. BUY THEIR PRETTY RED SILICONE 727 GASKET. ..IT GOEZ ON ABSOLUTELY DRY, TORQUES TO 12 INCH POUNDZ. DO IT AND YOU CAN GO MERRILY DOWN THE ROAD WITH NO LEAKZ FROM THAT SOURCE, EVER. Jer
 
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