The Ford Torino Page Homepage
Forum Home Forum Home > Powertrain Specific Forum > Transmissions
  New Posts New Posts RSS Feed - C6 Trans Leak
  FAQ FAQ  Forum Search   Events   Register Register  Login Login

C6 Trans Leak

 Post Reply Post Reply
Author
Message
72FordGTS View Drop Down
Admin Group
Admin Group
Avatar
GTS.org Admin

Joined: 06-September-2005
Location: Ontario, Canada
Status: Offline
Points: 5802
Post Options Post Options   Thanks (0) Thanks(0)   Quote 72FordGTS Quote  Post ReplyReply Direct Link To This Post Topic: C6 Trans Leak
    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
Back to Top
pete rad View Drop Down
Senior Member
Senior Member


Joined: 29-November-2014
Location: usa
Status: Offline
Points: 305
Post Options Post Options   Thanks (0) Thanks(0)   Quote pete rad Quote  Post ReplyReply Direct Link To This Post Posted: 11-August-2021 at 12:57PM
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.

Back to Top
californiajohnny View Drop Down
Moderator Group
Moderator Group
Avatar

Joined: 05-October-2013
Location: winlock, wa
Status: Offline
Points: 14606
Post Options Post Options   Thanks (0) Thanks(0)   Quote californiajohnny Quote  Post ReplyReply Direct Link To This Post Posted: 11-August-2021 at 1:24PM
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
Back to Top
aquartlow View Drop Down
Senior Member
Senior Member


Joined: 19-December-2011
Location: Summerfield, Fl
Status: Offline
Points: 2270
Post Options Post Options   Thanks (0) Thanks(0)   Quote aquartlow Quote  Post ReplyReply Direct Link To This Post Posted: 11-August-2021 at 2:57PM
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.
Back to Top
72 RS 351 View Drop Down
Senior Member
Senior Member
Avatar

Joined: 04-September-2014
Location: Knoxville TN
Status: Offline
Points: 2765
Post Options Post Options   Thanks (0) Thanks(0)   Quote 72 RS 351 Quote  Post ReplyReply Direct Link To This Post Posted: 11-August-2021 at 3:07PM
Originally posted by pete rad pete rad wrote:

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.



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
Back to Top
piper62j View Drop Down
Member
Member
Avatar

Joined: 21-July-2018
Location: 34613
Status: Offline
Points: 116
Post Options Post Options   Thanks (0) Thanks(0)   Quote piper62j Quote  Post ReplyReply Direct Link To This Post Posted: 12-August-2021 at 1:51PM
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.
Back to Top
Rockatansky View Drop Down
Senior Member
Senior Member


Joined: 30-July-2010
Location: On The Road
Status: Offline
Points: 6059
Post Options Post Options   Thanks (1) Thanks(1)   Quote Rockatansky Quote  Post ReplyReply Direct Link To This Post Posted: 13-August-2021 at 8:40AM
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 Wink
72 GT Ute
   
Back to Top
aquartlow View Drop Down
Senior Member
Senior Member


Joined: 19-December-2011
Location: Summerfield, Fl
Status: Offline
Points: 2270
Post Options Post Options   Thanks (0) Thanks(0)   Quote aquartlow Quote  Post ReplyReply Direct Link To This Post Posted: 13-August-2021 at 2:10PM
Originally posted by Rockatansky Rockatansky wrote:

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 Wink
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.
Back to Top
Rockatansky View Drop Down
Senior Member
Senior Member


Joined: 30-July-2010
Location: On The Road
Status: Offline
Points: 6059
Post Options Post Options   Thanks (0) Thanks(0)   Quote Rockatansky Quote  Post ReplyReply Direct Link To This Post Posted: 13-August-2021 at 2:11PM
that's the one
72 GT Ute
   
Back to Top
72FordGTS View Drop Down
Admin Group
Admin Group
Avatar
GTS.org Admin

Joined: 06-September-2005
Location: Ontario, Canada
Status: Offline
Points: 5802
Post Options Post Options   Thanks (0) Thanks(0)   Quote 72FordGTS Quote  Post ReplyReply Direct Link To This Post Posted: 14-August-2021 at 2:32AM
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
Back to Top
Rockatansky View Drop Down
Senior Member
Senior Member


Joined: 30-July-2010
Location: On The Road
Status: Offline
Points: 6059
Post Options Post Options   Thanks (1) Thanks(1)   Quote Rockatansky Quote  Post ReplyReply Direct Link To This Post Posted: 14-August-2021 at 4:56AM
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
   
Back to Top
handsofstone View Drop Down
Senior Member
Senior Member


Joined: 13-April-2018
Location: Northeast
Status: Offline
Points: 3941
Post Options Post Options   Thanks (0) Thanks(0)   Quote handsofstone Quote  Post ReplyReply Direct Link To This Post Posted: 14-August-2021 at 2:56PM
   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.
Back to Top
72FordGTS View Drop Down
Admin Group
Admin Group
Avatar
GTS.org Admin

Joined: 06-September-2005
Location: Ontario, Canada
Status: Offline
Points: 5802
Post Options Post Options   Thanks (0) Thanks(0)   Quote 72FordGTS Quote  Post ReplyReply Direct Link To This Post Posted: 15-August-2021 at 10:37AM
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
Back to Top
handsofstone View Drop Down
Senior Member
Senior Member


Joined: 13-April-2018
Location: Northeast
Status: Offline
Points: 3941
Post Options Post Options   Thanks (0) Thanks(0)   Quote handsofstone Quote  Post ReplyReply Direct Link To This Post Posted: 15-August-2021 at 10:41AM
  Do the arm seals while the pan is down. Peen the holes in the pan and use a cork gasket.
Back to Top
AUS GTS View Drop Down
Senior Member
Senior Member
Avatar

Joined: 26-July-2021
Location: Australia
Status: Offline
Points: 383
Post Options Post Options   Thanks (0) Thanks(0)   Quote AUS GTS Quote  Post ReplyReply Direct Link To This Post Posted: 15-August-2021 at 11:40AM
Could it be the shifter seal when youre actually shifting?? just a thought....
Al
Back to Top
72 RS 351 View Drop Down
Senior Member
Senior Member
Avatar

Joined: 04-September-2014
Location: Knoxville TN
Status: Offline
Points: 2765
Post Options Post Options   Thanks (0) Thanks(0)   Quote 72 RS 351 Quote  Post ReplyReply Direct Link To This Post Posted: 15-August-2021 at 11:41AM
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
Back to Top
handsofstone View Drop Down
Senior Member
Senior Member


Joined: 13-April-2018
Location: Northeast
Status: Offline
Points: 3941
Post Options Post Options   Thanks (0) Thanks(0)   Quote handsofstone Quote  Post ReplyReply Direct Link To This Post Posted: 15-August-2021 at 1:21PM
  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. 
Back to Top
72 RS 351 View Drop Down
Senior Member
Senior Member
Avatar

Joined: 04-September-2014
Location: Knoxville TN
Status: Offline
Points: 2765
Post Options Post Options   Thanks (0) Thanks(0)   Quote 72 RS 351 Quote  Post ReplyReply Direct Link To This Post Posted: 15-August-2021 at 3:06PM
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
Back to Top
Rockatansky View Drop Down
Senior Member
Senior Member


Joined: 30-July-2010
Location: On The Road
Status: Offline
Points: 6059
Post Options Post Options   Thanks (0) Thanks(0)   Quote Rockatansky Quote  Post ReplyReply Direct Link To This Post Posted: 15-August-2021 at 3:49PM
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
   
Back to Top
 Post Reply Post Reply

Forum Jump Forum Permissions View Drop Down

Forum Software by Web Wiz Forums® version 12.06
Copyright ©2001-2023 Web Wiz Ltd.

This page was generated in 0.156 seconds.