C6 Trans Leak |
Post Reply |
Author | |
72FordGTS
Admin Group GTS.org Admin Joined: 06-September-2005 Location: Ontario, Canada Status: Offline Points: 5802 |
Post Options
Thanks(0)
Posted: 11-August-2021 at 12:20PM |
I have noticed after the rebuild of my C6, it has had a minor leak at the pan. It was built with a Broader kit, which included a new steel deep pan and a cork gasket. The leak isn't big enough to drip, but after a couple of weeks the pan has a coating of ATF on it, and on the bolts around the perimeter. I torqued all the bolts to Ford specs. So I thought it was the gasket, and changed to a Fel-Pro paper/fiber type gasket. and retorqued. It's a bit better, but still leaking.
I checked the transmission fill tube, servo, cooler lines, and all other areas and don't see or feel any other leaks. So it seems to be coming from the pan itself. The pan rail is straight and undamaged. Any ideas?
|
|
Vince
1972 Ford GTS Sportsroof - Survivor, One Family car GTS.org Admin |
|
pete rad
Senior Member Joined: 29-November-2014 Location: usa Status: Offline Points: 305 |
Post Options
Thanks(0)
|
Did you check the shifter shaft seal and O ring for leakage? The shifter shaft seal and o ring are located on the drivers side of the trans above the pan, where the shifter linkage enters the trans. You can wipe the trans pan dry with a rag or towel, and see if the leak in coming down from the seal and o ring.
|
|
californiajohnny
Moderator Group Joined: 05-October-2013 Location: winlock, wa Status: Offline Points: 14606 |
Post Options
Thanks(0)
|
i've seen it seep right through the gaskets before???...
|
|
JOHN
74 GRAN TORINO S&H CLONE 74 VETTE CUSTOM 90 S10 BLAZER 4X4 LIFTED 77 CELICA CUSTOM 75 V8 MONZA SUPERCHARGED 79 COURIER VERT. SLAMMED 75 VEGA V6 5 SPD 70 CHEV C10 P/U 68 MUSTANG FB CONVERSION |
|
aquartlow
Senior Member Joined: 19-December-2011 Location: Summerfield, Fl Status: Offline Points: 2270 |
Post Options
Thanks(0)
|
Hey Vince, FWIW I have omitted trans oil pan gaskets on a couple different vehicles I own and used Red high temp silicone with absolutely no leaks. I will admit it makes an oil/filter change a bit more involved but still not bad. I realize a gasket is the preferred way to seal a trans pan, but the high temp silicone is an option that does work great. Hope this helps
|
|
www.supermotors.net/22468
Yeah, It's a Hybrid...It burns gas and tires. No matter how good she looks, somebody, somewhere, is tired of her sh*t. Beauty is skin deep, ugliness goes clear to the bone. |
|
72 RS 351
Senior Member Joined: 04-September-2014 Location: Knoxville TN Status: Offline Points: 2765 |
Post Options
Thanks(0)
|
I also would start with the shaft seals in the side, those will leak if they are old and didn't get replaced. Do any of the old Ford transmissions have non cork gaskets available? I don't plan to use cork gaskets ever again if I can help it. I would do the RTV if there was nothing but cork crap. But I don't recall having big issues way back when I did drive my old Fords and stock transmissions(C4 and C6).
|
|
Don
73 Ranchero "Sport 72 front end", floor shift/console, planning EFI 7000+ rpm 351-4V &4R70W 73 Ranchero GT 351C-4V &4R70W for sale later. 92 Lincoln Mark VII SE GTC, OBDII 347/4R70W |
|
piper62j
Member Joined: 21-July-2018 Location: 34613 Status: Offline Points: 116 |
Post Options
Thanks(0)
|
If the leak is around the pan, it really doesn't matter what the gasket material is.. The trick to getting a good seal is to take the time to dimple down each bolt hole in the pan. With the pan facing upward, support the flange with a block of wood, using a small ballpeen hammer (ball end on the pan) and tap downward on each hole so that there is a slight indentation. This actually raises the bolt hole slightly from the underside. This procedure will allow the bolts to pull tighter on the pan, when torqued down and sealing it all around. We did this at our shop on every pan that was steel.. It doesn't work well on aluminum pans. You can also thinly spread silicone on the clean mating surfaces, but wait until the silicone is almost dry. Otherwise, the wet silicone will allow the gasket to slip as if it were being squashed out preventing a tight seal.
|
|
Rockatansky
Senior Member Joined: 30-July-2010 Location: On The Road Status: Offline Points: 6059 |
Post Options
Thanks(1)
|
Sonnax to the rescue! click on Find A Dealer, it looks like there's some up dere by you eh? i have one here somewhere in my pile-o-chit, i'd have a nice drain plug welded into the side before installing
|
|
72 GT Ute
|
|
aquartlow
Senior Member Joined: 19-December-2011 Location: Summerfield, Fl Status: Offline Points: 2270 |
Post Options
Thanks(0)
|
Great info! I bought this one for my c6 years ago, along with a few other parts. http://www.transmissionpartsusa.com/Ford_C6_transmission_oil_pan_p/400-003695001.htm Good place to purchase C6 parts on the cheap(usually).
|
|
www.supermotors.net/22468
Yeah, It's a Hybrid...It burns gas and tires. No matter how good she looks, somebody, somewhere, is tired of her sh*t. Beauty is skin deep, ugliness goes clear to the bone. |
|
Rockatansky
Senior Member Joined: 30-July-2010 Location: On The Road Status: Offline Points: 6059 |
Post Options
Thanks(0)
|
that's the one
|
|
72 GT Ute
|
|
72FordGTS
Admin Group GTS.org Admin Joined: 06-September-2005 Location: Ontario, Canada Status: Offline Points: 5802 |
Post Options
Thanks(0)
|
Thank you guys, some great info here. Piper62j, I like that idea of dimpling the pan. I may try that first. I also checked around the shifter seal and it was a bit damp there. I cleaned it up with solvent and will see if it is actually coming from that seal or not. If it is, it is very, very, minor. I still think it is the pan and gasket as the entire perimeter of the pan has fluid on it. Again, the leak is minor overall, but I want it bone dry.
I searched around the internet, and found pan gaskets leaks very common on the C6. Some suggested that LubeLocker gasket will fix any pan leaks. Pricey, but it if works it might be worth it. And cheaper than upgrading to a cast aluminum pan, although I do wish this pan from the broader kit had a drain bolt.
|
|
Vince
1972 Ford GTS Sportsroof - Survivor, One Family car GTS.org Admin |
|
Rockatansky
Senior Member Joined: 30-July-2010 Location: On The Road Status: Offline Points: 6059 |
Post Options
Thanks(1)
|
the inner kickdown shaft is notorious for seeping, and super easy to double up the O ring, just add another there's plenty of room. i forget if there's room for a 2nd seal for the linkage arm in the case or not? one bud used baby powder as a tell for whether there was seepage going on the LubeLocker gasket does look sweet but i wouldn't bother if the pan itself isn't up to the task of holding it tight. if it does turn out to be the pan gasket i'd go with the Sonnax pan and a composite type gasket like the late model cars used. from the pics i'd say these are the same gasket but ? Edited by Rockatansky - 14-August-2021 at 5:09AM |
|
72 GT Ute
|
|
handsofstone
Senior Member Joined: 13-April-2018 Location: Northeast Status: Offline Points: 3941 |
Post Options
Thanks(0)
|
The best way to dimple the pan holes is to lay the pan edge on a piece of wood, place the ball end of a ball peen hammer on it and use a rubber mallet to give the hammer a whack. Go easy, you just want to create even tension for the gasket surface.
|
|
72FordGTS
Admin Group GTS.org Admin Joined: 06-September-2005 Location: Ontario, Canada Status: Offline Points: 5802 |
Post Options
Thanks(0)
|
I put about 100 miles on the car over the weekend. It was most wet at the rear of the pan, but just a very light coating of fluid. There was some very tiny seepage at the shifter seal, but definitely not enough to be my issue. So I am thinking it is the pan and gasket.
|
|
Vince
1972 Ford GTS Sportsroof - Survivor, One Family car GTS.org Admin |
|
handsofstone
Senior Member Joined: 13-April-2018 Location: Northeast Status: Offline Points: 3941 |
Post Options
Thanks(0)
|
Do the arm seals while the pan is down. Peen the holes in the pan and use a cork gasket.
|
|
AUS GTS
Senior Member Joined: 26-July-2021 Location: Australia Status: Offline Points: 383 |
Post Options
Thanks(0)
|
Could it be the shifter seal when youre actually shifting?? just a thought....
|
|
Al
|
|
72 RS 351
Senior Member Joined: 04-September-2014 Location: Knoxville TN Status: Offline Points: 2765 |
Post Options
Thanks(0)
|
If it's wet around the shifting lever etc, then it will be leaking from there and cause the area below and the pan to be wet. Your pan might be 80% or more of the big wetness you are hunting. Those shaft seals I think will all be done by removing the large nut inside on the inner end of that lever, to R&R the shaft and the connected parts. So when you drop the pan, be ready with the seals and some patience to work with that group of parts on the shift lever etc. |
|
Don
73 Ranchero "Sport 72 front end", floor shift/console, planning EFI 7000+ rpm 351-4V &4R70W 73 Ranchero GT 351C-4V &4R70W for sale later. 92 Lincoln Mark VII SE GTC, OBDII 347/4R70W |
|
handsofstone
Senior Member Joined: 13-April-2018 Location: Northeast Status: Offline Points: 3941 |
Post Options
Thanks(0)
|
Dropping the valve body and getting the kickdown rod out of the way allows you to replace the seal usins a fine threaded bolt and washers. Pounding them in is never a good idea if it can be avoided.
|
|
72 RS 351
Senior Member Joined: 04-September-2014 Location: Knoxville TN Status: Offline Points: 2765 |
Post Options
Thanks(0)
|
I have never worked on a C6, I figured the parts would generally come apart the same way. I hope to work on mine some day next year, to do a VB kit and adjust the shifting etc.
|
|
Don
73 Ranchero "Sport 72 front end", floor shift/console, planning EFI 7000+ rpm 351-4V &4R70W 73 Ranchero GT 351C-4V &4R70W for sale later. 92 Lincoln Mark VII SE GTC, OBDII 347/4R70W |
|
Rockatansky
Senior Member Joined: 30-July-2010 Location: On The Road Status: Offline Points: 6059 |
Post Options
Thanks(0)
|
transman is going to either just jam a pick into the outer seal and wrangle it out, or drill a small hole into it if necessary then wrangle it out with a pick tool. install new seal by any means available, hopefully some kind of tube style seal driver, like a deep socket inner shaft O ring should come out with gentle pick work also, definitely double up just sayin the modulator is dry Vince?
|
|
72 GT Ute
|
|
Post Reply | |
Tweet |
Forum Jump | Forum Permissions You cannot post new topics in this forum You cannot reply to topics in this forum You cannot delete your posts in this forum You cannot edit your posts in this forum You cannot create polls in this forum You cannot vote in polls in this forum |