Need to replace trans pan gasket, maybe?

polara10x500

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69 Polara 500 vert, has a nice aftermarket pan, TCI alum pan, deep, cast alum, drain plug, but recently has developed a leak on pass side. Checked all around trans several days now after wiping fluid off just to make sure it's coming from pass. side at the pan gasket only. Today wiped it one more time and gave it just a little torque on just those 4 bolts to see if it improves any tomorrow. Car has been great up until this past fall and colder weather through winter. last start up and a good drive around was back about Oct. before putting away for cold weather and did not look because all has been good until looking under recently. Anyway gasket has never looked quite right on that side since inspecting car at time of purchase around Jan. 2020 but trans has always been dry until recently. Just to make sure and look periodically under the car time to time I check things like the trans speedo seal, trans line connections, trans dip stick seal, shifter shaft seal, other plugs that are in there but not being used, all is good and dry above the pan. Searching for that place in TN that I've seen on here and other websites but can't remember. Keeping an eye on trans, not liking drip or two a day, rest of car is dry everywhere else which is an accomplishment, new when bought or restored recently. Thanks for any input and advice,
 
Go to your Dodge dealer parts counter and ask for a reusable trans pan gasket that has a metal framewith rubber both sides for a late 90's early 2000's A518 OD trans.. Same gasket as 727.
Never leaks.
Hope this helps.
 
G'Day,
At the Mention of REAL Gaskets I'll take the Opportunity to Ask.
I Bought a Set of R/Cover Gaskets (& Trans Pan / Sump Gaskets) from REAL, Just about to Replace a Set of Heads.
My Mech Scoffed a Little When I mentioned the REAL Gaskets.
I Don't want to "RISK" Being "I Told You Soed" If You Know What I Mean.
Any One Had Problems with These Leaking?
I Realise the Idea is to Tighten Them Down Gently.
But Do They Meet Expectations?
T.I.A. for Any Advice.
Regards Tony.M
(P.S. Apologies if I Appear to be Hi-Jacking the Thread, Not My Intention!)
 
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69 Polara 500 vert, has a nice aftermarket pan, TCI alum pan, deep, cast alum, drain plug, but recently has developed a leak on pass side. Checked all around trans several days now after wiping fluid off just to make sure it's coming from pass. side at the pan gasket only. Today wiped it one more time and gave it just a little torque on just those 4 bolts to see if it improves any tomorrow. Car has been great up until this past fall and colder weather through winter. last start up and a good drive around was back about Oct. before putting away for cold weather and did not look because all has been good until looking under recently. Anyway gasket has never looked quite right on that side since inspecting car at time of purchase around Jan. 2020 but trans has always been dry until recently. Just to make sure and look periodically under the car time to time I check things like the trans speedo seal, trans line connections, trans dip stick seal, shifter shaft seal, other plugs that are in there but not being used, all is good and dry above the pan. Searching for that place in TN that I've seen on here and other websites but can't remember. Keeping an eye on trans, not liking drip or two a day, rest of car is dry everywhere else which is an accomplishment, new when bought or restored recently. Thanks for any input and advice,
The Mopar gasket mentioned by @cbarge is Part #2464324AC. I have a buddy that was building Mopar race transmissions that swears by them.

That said... A lot of pan gasket leaks turn out to be the seal around the selector shaft... and yea, I know, that's on the driver side, but the ATF drips down and can migrate around the pan lip and drip off about anywhere. If you're swapping the gasket anyway, you can pull the valve body and swap new seals in pretty easy. One small seal is on the throttle shaft and one (the one that usually leaks) is in the case. You can do it without pulling the valve body, but you'll need a tool. IMHO, it's easier if you take the valve body out.

Another culprit, and this is on the passenger side, is the dip stick tube seal. This is an O-ring seal that often gets a cheap O-ring replacement that degrades and starts leaking. You need to get the correct ring that won't break down... and again, this is an easy fix when the pan is off (although the pan really doesn't need to come off to change it). It also can drip down and look like a pan gasket.

Regarding the Real gasket, I tried one of their silicone trans gaskets on a 904 and I couldn't get it to seal. Lot's of guys swear by them, but my experience wasn't good. It's fussy about any oil on it and how it's torqued. The Mopar gasket I listed is reusable, easy to use and it seals just fine. IMHO, it's just a much better gasket.

Some discussion and options on the shaft seal here: TF 727 "How To" shift lever seal replacement
 
G'Day,
At the Mention of REAL Gaskets I'll take the Opportunity to Ask.
I Bought a Set of R/Cover Gaskets (& Trans Pan / Sump Gaskets) from REAL, Just about to Replace a Set of Heads.
My Mech Scoffed a Little When I mentioned the REAL Gaskets.
I Don't want to "RISK" Being "I Told You Soed" If You Know What I Mean.
Any One Had Problems with These Leaking?
I Realise the Idea is to Tighten Them Down Gently.
But Do They Meet Expectations?
T.I.A. for Any Advice.
Regards Tony.M
(P.S. Apologies if I Appear to be Hi-Jacking the Thread, Not My Intention!)
Valve cover gaskets from REAL leaked for me.
 
There is a small o ring on a shaft that is pushed into back of tranny body. It holds the rear band in place and is covered by the rear extension housing. It can also leak from there and travel or drip.
 
Mine has leaked at the selector, easy fix. Now I have one at the band pin for lack of a better term. Not so easy & it leaks quite a bit. Arghhh!
 
I feel for you Alrui!
It is not an easy fix but can be done in car.
First if small block , move distributer cap off to side so it doesnt crack when you take driveshaft and crossmember off and egine moves down at back.The extension housing has to come off as well as tranny pan and valve body.
You can then get at the band pin. If lucky and not seized in you can move with a punch. The pin only has to move out about an inch to rrplace o ring. Again if careful the band support should stay in place and simply push pin back with new o ring. If not you will have to reset band and band strut.
All that work for 2 cent o ring!
 
I feel for you Alrui!
It is not an easy fix but can be done in car.
First if small block , move distributer cap off to side so it doesnt crack when you take driveshaft and crossmember off and egine moves down at back.The extension housing has to come off as well as tranny pan and valve body.
You can then get at the band pin. If lucky and not seized in you can move with a punch. The pin only has to move out about an inch to rrplace o ring. Again if careful the band support should stay in place and simply push pin back with new o ring. If not you will have to reset band and band strut.
All that work for 2 cent o ring!
Thanks for the info! This is a 383 so no worry about the cap but great info nonetheless:)
 
Drained trans last week so leaks would stop while waiting for real gasket to arrive. Haven't dropped pan yet eighter till I'm ready to seal and refill. REAL G says no sealant is needed but I'm thinking I should anyway. Also warmer temps in a few days here in TN will help, its cold here. Torque specs anyone? Still waiting for info from TCI. Hoping to seal this pan one time and be done so I can move on to the next project. All advice is appreciated as always. Thanks.
 
Drained trans last week so leaks would stop while waiting for real gasket to arrive. Haven't dropped pan yet eighter till I'm ready to seal and refill. REAL G says no sealant is needed but I'm thinking I should anyway. Also warmer temps in a few days here in TN will help, its cold here. Torque specs anyone? Still waiting for info from TCI. Hoping to seal this pan one time and be done so I can move on to the next project. All advice is appreciated as always. Thanks.
I would refrain on sealer particularly silicone. Im my experience sealer creates more problems then it solves especially on transmission pan gaskets. That said per the FSM the torque on the pan bolts is 150 inch pounds (12.5 ft pounds).
 
REAL G says no sealant is needed
That is correct. It even has to be 100% free of trans fluid.
Torque specs anyone?
The torque specs will come with the gasket. It's really low... lower than the factory specs... Something like 25 in/lbs.

IMHO, The Mopar gasket is a lot less "fussy".
 
Good looking gasket, gonna follow their instructions on the install as both of you also, DRY and clean. Thay even bold letter DRY on instructions. Torque says 20 to 25 in/lbs also. At least I can redo with some sealant if first time doesn't work. Still have clean fluid to put back in, lost a 1/2 cup maybe since been leaking but it's clean and shouldn't have to buy new fluid. Anymore advice? Big J.. Alrui. Like I said CLEAN an DRY put it on and torque to 20 to 25 in/lbs. fill her up and look for leaks then fire up and look for leaks. Crossing my fingers, thanks again fellas.
 
Your plan is good, go by the manufacturers instructions and go from there. Careful not to over fill the trans, start out a little low as when ATF warms up it expands. Overfilled is bad as it will be more prone to burning the fluid.
 
I put the real gaskets on my valve covers and transmission pan. Valve covers haven’t seeped a drop after 3 years and about 6,000 miles.
The transmission gasket has a little seep. I will be the first to say that my car transmission pan has been beaten a couple of times, I probably didn’t get it as straight as I should. In the summer when I am driving it regularly, I only see a little sheen. But when it sits in the winter I will get a couple of drops in a month. I do have a new shifter seal.
 
Thanks Alrui, I do the same, I sneak up on my fluid levels when topping off and warming up. I hope that this works first time, leaks are the worst. Tanks.
 
Thats great to hear feedback on the positive HWYCRZR because most is good for REAL G. I'm hoping I have luck and have good results. I want quality parts from USA. Don't want crap on my 69, I want to have a good time not problems with fixing a 50 year old car all the time with chi crap.
 
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