Stock pan, with a gromet style seal, works every time. See post #12 in the below link.
727 dipstick tube leak
727 dipstick tube leak
Would a billet aluminum transmission pan be worth getting?
- Thread starter Gerald Morris
- Start date
I tried one of those silicone gaskets on my 904 in my '65 Barracuda. I changed the upper valve body to a later, part throttle downshift version.
I wish I could say that it worked, but it's been a dismal failure. I can't get it to stop leaking. Tried different torque etc. Yea, 25 in/lbs... Cleaned everything real well... Just like the directions say. Had it off and back on. The fluid leaks fast enough to watch it drip.
The gasket that was on it was just lightly glued to the pan with no leaks. The pan is in good shape, no bends or problems.
I used the reusable Mopar gasket that people here and a couple friends recommend for a 727 on my 300. No leaks at all... and I have had that one off once and reused it. I found that Lube Locker made a very similar one for the 904 and that should be here sometime today.
For my money, the 727 gets the Mopar gasket, hands down. I have a buddy that builds 727 transmissions that swears by them. Part #2464324AC.
The silicone gasket may work great with other transmissions, but it's not working with my 904.
I wish I could say that it worked, but it's been a dismal failure. I can't get it to stop leaking. Tried different torque etc. Yea, 25 in/lbs... Cleaned everything real well... Just like the directions say. Had it off and back on. The fluid leaks fast enough to watch it drip.
The gasket that was on it was just lightly glued to the pan with no leaks. The pan is in good shape, no bends or problems.
I used the reusable Mopar gasket that people here and a couple friends recommend for a 727 on my 300. No leaks at all... and I have had that one off once and reused it. I found that Lube Locker made a very similar one for the 904 and that should be here sometime today.
For my money, the 727 gets the Mopar gasket, hands down. I have a buddy that builds 727 transmissions that swears by them. Part #2464324AC.
The silicone gasket may work great with other transmissions, but it's not working with my 904.
Yes it is on a smaller scale. Used to be Labeled the fastest 1/2 mile dirt track in the Midwest. Now they changed it to 3/8 mile. It closed down for a while but Donnie Shatz (World of Outlaws) invested in it and changed the configuration. Actually last week or so they had an outlaws race there.
So far so good. I don’t like adding goo to gaskets either. I was diligent in using paint prep to clean off any oil on the surfaces. Ask me in a couple of years. Did the valve covers as well.
Big Terry
New Member
All I ever used/use is the original cork gasket,no sealer,if pans square and bolts not over tightened they don't leak,they didn't when new.
Gerald Morris
Senior Member
I know of the gasket company you extol and I DID consider them! I opted for the Moroso gasket because they combine silicone with steel at 3/16" thickness. I WILL take the UTMOST CARE TORQUING my pan bolts too! This matter cannot be over-emphasized with neophyte tranny-pan fixers, ESPECIALLY WITH SILICONE GASKETS.
In any case, the Moroso gasket awaits my attentions HERE, NOW, so IFF the current monsoon cool speel will persist until this weekend, I may avail myself of it and some fresh Type F fluid and filter then too.
I LOVE the idea of a gasket which can endure more than one application. I also HATE having my machine down for 24 hours to let RTV set, but know that if necessary, I will give it that full 24. Pray with me that the Old Pueblo gets some NORMAL September weather this year, so I can test the Moroso gasket and some of the hypotheses buzzing in my bonnet....
Gerald Morris
Senior Member
Thx for the nice comparative display of gasket types. I went through all of those either on my old Disgustang years ago, or Mathilda the first year I drove her. Again, I commend you for this arrangement on our behalves.
Gerald Morris
Senior Member
I've enjoyed good success with timing chain covers, water pumps and such, finding that scrupulous cleaning the surfaces and checking with good straight edges and planes helps insure a good seal. I use RTV more often than not, usually sparingly. This transmission was very difficult to seal in 2016-17. The fact that it didn't lose a drop of fluid until this summer impresses me with the shop that rebuilt it for me to no end. Even the Ford FMX, C4s and C6s of my youth weren't so difficult! I even did a Chevy Hydramatic on a 64 El Camino that sealed more easily. (Or being stoned to not giving a **** about a quart a week of fluid at times may have tinctured my memory of some of this hazy past....cough!)
Be all this as it was, I might get a plate of good polyacrylate sheet or heavy glass to check the surface of this transmission once the pan is off. I just can't spend much time chasing rabbits down sundry holes right now. Lets see what this Moroso gasket will do for me with the nice little stamped steel pan I got. I DO plan to wash the tranny first with plenty degreasing/cleaning solvent(s) in order to see better the problem regions.
Gerald Morris
Senior Member
I went for the Moroso gasket this time after having tried the Mopar MOPAR 02464324AC gasket back on 10-28-2016. (Computers are HANDY for keeping receipts!) That one is a good gasket, but didn't quite stop the fluid loss. The Lube Locker made it to my Top 5 Contender List this time around also. I ruled it out because its a little thin. All three gaskets I've named have some reinforcing middle stratum to help hold them true to the shape and surfaces of the transmission and pan. One criticism of the pure silicone gaskets I've seen is that they lack this, and are apt to get sucked into the transmission at times due to this lack.
I'd best start my Novena to St. Joe the Mechanic that this doesn't devolve into some latter day saga....
3175375
Senior Member
@Gerald Morris , you are quite the constructor of sentences. Me like!
Regarding gasket sealing, I have had success in using Permatex High-Tack and Fel-Pro gaskets.
However, my best success is on my Mustang valve covers, where I used the later model Viton with a steel ‘ring’ gasket, filed down the lip on the face of a set of Cobra valve covers and silicon grease.
I was pleased as punch when it came time to remove the valve covers (due to a likely Chinesium TRW rocker arm Breaking during an open track event). I simply unbolted the valve cover, re-applied a bit of silicon grease and re-attached said valve cover and gasket. Done, with no leaks!
I did install the Lube Locker yesterday and it's thinner than I expected. Quite frankly, I thought it would be an aftermarket version of the Mopar piece, but it falls short of that. Being a 904, my choices are limited. Moroso doesn't make a gasket for the 904, so that's not a consideration for me.
The core is aluminum rather than steel, that may or may not be better. The beading doesn't stand very proud of the surface, but it looks good.
Bottom line is that after a night with a fresh piece of cardboard under it to show drips, it seems to have done the job. I also liked that the gasket isn't as fussy about torque specs. I think that the low torque in the Tennessee gasket procedure just isn't enough to pull the pan down tight enough to seal the gasket. Too much and the gasket distorts, so hitting the "sweet spot" where it seals, yet doesn't squeeze out, may be hard to do. I lost over a quart of fluid into the drip pan while I waited 5 days for the new gasket to show up.
Thatz why the Lord gave us choices of Blondes, Brunettes, and Red Heads. I'll leave you with one more about silicone my new friend. There are times and instances when Gorilla Snot in a tube iz the only choice and rightfully so, ie: cornerz of valley pan gaskets, timing chain coverz in in cornerz of 318s between the block and pan behind those coverz and a few other places that escape me memory rite now. Mother Mopar Part Counters sells a 3 oz tube of that Gorilla Snot that they tag ATF-RTV Part # 05010884AA, and I know for sure because I have friendz behind a few of those parts counters that tell me that factory wrenches from the Bow Tie and Blue Oval camps show up from time to time to keep a tube of that Mopar Gorilla Snot in their tool chests at work when they need the good stuff. BTW, This stuff iz the "let it stand for 24 hourz stuff", Jer
Gerald Morris
Senior Member
Good to know! The black and grey stuff I've been using for the timing chain cover, valve covers et al requires that 24 hour cure time too. Some times one simply MUST wait.
Gerald Morris
Senior Member
I rigorously researched the Lube Locker for my 727 before settling on the Moroso gasket. Installed that this morning, following their instructions available on JEGS for the Moroso aluminum pan made to complement that gasket. Thus far, (mere 4 hours in AZ sunshine) not so much as a drop of transmission fluid has shown outside the transmission. This bodes well enough, given what it is, but I will test with Rigor AND Vigor this evening, zooming down I-19, using the passing gear, then some serious idiot traffic after warming up the new fluid well.
(Age sets in. I ALSO will carry in the trunk an extra gallon of fresh fluid, in case of djinn, leprechauns, gremlins or suchlike causing sudden, catastrophic fluid loss.)
If the torture test goes well, then I will pronounce these Moroso silicone-rubber + steel sandwiches a Great Boon to The Moparian Brotherhood, for our benefit, not Moroso's capitalist interest.
I'm going to walk this back a bit.
The new gasket was dry for a couple days and then I had all sorts of fluid that had dripped out.
I happened to see something laying on the floor and realized what had happened. It was the throttle shaft seal.
The '65 904 trans in my car is cable shifted. The throttle linkage comes into the top of the trans and uses the same seal as the later one does to seal it to the valve body, except in this case, it seals it to the case. When I put the valve body back in, I knocked the seal out.
Big duh moment for me. It was OK until the fluid drained back into the pan from the converter etc., but when it did, and the fluid got as high as the seal, it poured out.
Put the seal back in place, which was pretty simple, and no more leak.
So... I may have been too hasty to blame the silicone gasket. That said, I do like the Lube Locker gasket a little better as it's not as fussy about fastener torque.
Gerald Morris
Senior Member
What LAUDABLE HUMILITY you've demonstrated here Big John !!! You rate a Golden Pentastar for the Day for this one Sir.
Do you think the cable linked 1965 (and earlier, but especially the 1965 ones) can readily be adapted to use a B & M floor shifter or such? It occurs to me that such a scheme for the right C body may work toward creating a pickup truck based on the car body similar to the Ranchero or even the ultra RARE Imperial "flower-getter" once posted to this very Forum. NOT a show room project mind you, but as a practical work vehicle, such appeals to me.
I've had a couple B&M shifters in cars and I'm not real sure if the amount of travel at the shifter is the same as what is needed at the valve body. The cable floor shifter in my Barracuda works similar to the B&M shifter, so I would look for one of those if it were me. The console is small enough to fit just about anything.
Gerald Morris
Senior Member
GOOD TO KNOW!! Well, if I get about $20k with absolutely nothing more pressing to do with it, then I'll have to buy another mid 1960s C body ready for daily driving, and then a good oxy-acetylene rig to cut some serious sheetmetal off Mathilda, then weld where needed in order to convert her from Newport to "El Newporto." THEN I can call on you to sell me that shifter and console!
Nice Plan, eh? Should I make it $30k as the threshold money for this project?
MUCHAS Gracias!
Nice Plan, eh? Should I make it $30k as the threshold money for this project?
MUCHAS Gracias!
Gerald Morris
Senior Member
Update: 09/07/20 20:30 MST
Took Mathilda for her post fluid-change/gasket replacement run for 30 minutes. So FAR, ALL APPEARS VERY WELL! I detected not so much as a drop of fluid on the pan or around the gasket after the run through evening traffic, ambient temperature only ~95 F. This latter condition warrants continued observation throughout the coming week. I certainly DON'T want any more 110+ F afternoons, but if I get one, THEN will be the BEST time to look for leaks. That's the only normal condition which can drive the coolant temperature up to 210 F with the pusher running. (Deo gratias, that contains the temp curve, and should for the foreseeable future.)
Here are a few pics of this little operation, FWIW:
https://photos.app.goo.gl/JqUXmW85Nt4ZhiiZ8
https://photos.app.goo.gl/kUbrzWYu9tnNntwj9
Nice NEW Moroso gasket! Note the cheap rubber gaskets that came with the Dacron filter I copped from Advance Auto.
https://photos.app.goo.gl/uQpAwgaJkhqp9oA27
Tranny pan w OLD gasket, drip, drip, DRIP!!
https://photos.app.goo.gl/6RG9f3LAf1jRDjAd7
Pan, just post-removal, with much vaunted Mopar gasket, SLATHERED with black RTV still firmly stuck to pan. Credit where due: this arrangement held fluid for over 2 of the past 3 years very admirably, not losing a drop until March this year. Even had there been no leakage, I would have HAD to remove this pan to change fluid and filter. Note the nice big round magnets that Herman's put in. I had 3 small neodymium magnets visible at the upper side of this pic, which they generously supplemented. Note some signs of wear on the bottom of the pan. Filter also dark with debris. Should have done this job last Fall. Damnit!
Anyway, I removed, cleaned off and salvaged the Mopar gasket, for possible future use, washed out the pan nicely, scraped GENTLY the RTV from the gasket surface on the 55 yr old tranny, installed the new Moroso gasket, torqued the bolts to 120 in*lbs as per Moroso's spec, instead of 150 in.*lbs as specified in the FSM for the old school cork gaskets. Silicone gaskets all specify less torque (lower pressure) than rubber or fiber gaskets, so Moroso's spec didn't surprise me. I'll append pix of the completed job later this week, after I've run the new stuff for a 100 or so city miles. THEN we should KNOW if this new gasket suffices to stop the flow of precious fluid from this transmission. If there are no further leaks, I will totally replace this mix of Castrol Transmax and SuperTech Type F with a GOOD SYNTHETIC Type F for long term use. I'm researching several possible fluids, including Castrol, though I suspect B&M Trick Shift will get the ticket. (that might be mineral oil, but its a GOOD blend of them I read.....) If anyone knows of an outstanding synthetic Type F, I'm open to suggestions.
Thank all of you for your stimulating, worthy comments on this subject. As a final note, returning to the original subject of this thread, I see Moroso makes a cast aluminum pan doubtless made with this gasket in mind. JEGs vends this product, complete with propaganda touting its wonders, as can be seen here:
Moroso 42080: Aluminum Transmission Pan Chrysler Torqueflite 727 | JEGS
It remains to be seen whether its worthwhile to drop such coin on such a pan. Stay Tuned!
Post Scriptum: As usual, Google isn't playing nice with the Forum, so if you have trouble seeing the pics, then you can try the link below to get a look at what I so painstakingly posted above here:
https://photos.app.goo.gl/jpAiRe5nRLZXm5py5
I USED to give Google "White Hat" status, until Schmidt hired the current CEO. Wouldn't be sorry to see him dropped onto a busy Interstate frankly..... from say, 3 stories.
Took Mathilda for her post fluid-change/gasket replacement run for 30 minutes. So FAR, ALL APPEARS VERY WELL! I detected not so much as a drop of fluid on the pan or around the gasket after the run through evening traffic, ambient temperature only ~95 F. This latter condition warrants continued observation throughout the coming week. I certainly DON'T want any more 110+ F afternoons, but if I get one, THEN will be the BEST time to look for leaks. That's the only normal condition which can drive the coolant temperature up to 210 F with the pusher running. (Deo gratias, that contains the temp curve, and should for the foreseeable future.)
Here are a few pics of this little operation, FWIW:
https://photos.app.goo.gl/kUbrzWYu9tnNntwj9
Nice NEW Moroso gasket! Note the cheap rubber gaskets that came with the Dacron filter I copped from Advance Auto.
https://photos.app.goo.gl/uQpAwgaJkhqp9oA27
Tranny pan w OLD gasket, drip, drip, DRIP!!
https://photos.app.goo.gl/6RG9f3LAf1jRDjAd7
Pan, just post-removal, with much vaunted Mopar gasket, SLATHERED with black RTV still firmly stuck to pan. Credit where due: this arrangement held fluid for over 2 of the past 3 years very admirably, not losing a drop until March this year. Even had there been no leakage, I would have HAD to remove this pan to change fluid and filter. Note the nice big round magnets that Herman's put in. I had 3 small neodymium magnets visible at the upper side of this pic, which they generously supplemented. Note some signs of wear on the bottom of the pan. Filter also dark with debris. Should have done this job last Fall. Damnit!
Anyway, I removed, cleaned off and salvaged the Mopar gasket, for possible future use, washed out the pan nicely, scraped GENTLY the RTV from the gasket surface on the 55 yr old tranny, installed the new Moroso gasket, torqued the bolts to 120 in*lbs as per Moroso's spec, instead of 150 in.*lbs as specified in the FSM for the old school cork gaskets. Silicone gaskets all specify less torque (lower pressure) than rubber or fiber gaskets, so Moroso's spec didn't surprise me. I'll append pix of the completed job later this week, after I've run the new stuff for a 100 or so city miles. THEN we should KNOW if this new gasket suffices to stop the flow of precious fluid from this transmission. If there are no further leaks, I will totally replace this mix of Castrol Transmax and SuperTech Type F with a GOOD SYNTHETIC Type F for long term use. I'm researching several possible fluids, including Castrol, though I suspect B&M Trick Shift will get the ticket. (that might be mineral oil, but its a GOOD blend of them I read.....) If anyone knows of an outstanding synthetic Type F, I'm open to suggestions.
Thank all of you for your stimulating, worthy comments on this subject. As a final note, returning to the original subject of this thread, I see Moroso makes a cast aluminum pan doubtless made with this gasket in mind. JEGs vends this product, complete with propaganda touting its wonders, as can be seen here:
Moroso 42080: Aluminum Transmission Pan Chrysler Torqueflite 727 | JEGS
It remains to be seen whether its worthwhile to drop such coin on such a pan. Stay Tuned!
Post Scriptum: As usual, Google isn't playing nice with the Forum, so if you have trouble seeing the pics, then you can try the link below to get a look at what I so painstakingly posted above here:
https://photos.app.goo.gl/jpAiRe5nRLZXm5py5
I USED to give Google "White Hat" status, until Schmidt hired the current CEO. Wouldn't be sorry to see him dropped onto a busy Interstate frankly..... from say, 3 stories.
Last edited:
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