The Ford Barn

40cpe · 08-01-2013, 04:46 PM

I had a leak on my C-4 trans at the shift shaft. I took it to a transmission shop to get it stopped. I picked it up, took it home and parked it on a plastic sheet to check for leaks. The next morning it had a puddle under the drive shaft yoke and one under the rear of the pan. I took it back, told them to keep it until it would't drip. Two days alter they called and said it was ready. This time the yoke leak is gone, but the pan still drips. I'd rather fix it myself than deal with them again. The gasket they put on it is a rubber looking compound. My question is: Does a cork gasket seal any better? I'm thinking a cork gasket with a thin film of RTV sealer might do it. Any suggestions?

NH Ford nut · 08-01-2013, 08:19 PM

Your pan may be distorted.
Check for flange flatness, especially around the bolt holes.
I always use a skim of sealer around the gasket - cork or rubber.
Good luck.

Ole Don · 08-02-2013, 10:44 AM

There is a Permatex brand black sealer (Good Stuff?) that could be used here, but a new cork gasket should be less expensive. Make sure the pan is flat. Clean all the bolts on a wire wheel, and run a thread chasser in all the holes. Not a tap, they can remove metal. You only want to remove crud. Clean the pan with thinner or acetone, and the bottom of the trans too. Use 3M trim cement to glue the new gasket to the pan. Let it set and follow instructions. After its on the pan and set, soak the top of the gasket with WD 40. With a drop of WD 40 on each bolt, screw them in and tighten them only to where the gasket starts to squeeze out, no more. After a few heat cool cycles, you may give each bolt a half turn more.

40cpe · 08-02-2013, 06:05 PM

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I was back under the car checking it this afternoon. It looks like there is one pan bolt leaking at the head and dripping on the floor. The band adjustment on the right side is wet and red but no dripping yet. I think I can seal the bolt. Can the adjuster leak be repaired externally? Necessary to drain the fluid?

Thanks,
Gene

08-01-2013, 04:46 PM	#1
40cpe Senior Member Join Date: May 2010 Location: Star, MS Posts: 4,024	C-4 pan gasket material I had a leak on my C-4 trans at the shift shaft. I took it to a transmission shop to get it stopped. I picked it up, took it home and parked it on a plastic sheet to check for leaks. The next morning it had a puddle under the drive shaft yoke and one under the rear of the pan. I took it back, told them to keep it until it would't drip. Two days alter they called and said it was ready. This time the yoke leak is gone, but the pan still drips. I'd rather fix it myself than deal with them again. The gasket they put on it is a rubber looking compound. My question is: Does a cork gasket seal any better? I'm thinking a cork gasket with a thin film of RTV sealer might do it. Any suggestions?

08-01-2013, 08:19 PM	#2
NH Ford nut Junior Member Join Date: Jul 2013 Posts: 14	Re: C-4 pan gasket material Your pan may be distorted. Check for flange flatness, especially around the bolt holes. I always use a skim of sealer around the gasket - cork or rubber. Good luck.

08-02-2013, 10:44 AM	#3
Ole Don Senior Member Join Date: May 2010 Location: St. Michael, Minnesota Posts: 1,713	Re: C-4 pan gasket material There is a Permatex brand black sealer (Good Stuff?) that could be used here, but a new cork gasket should be less expensive. Make sure the pan is flat. Clean all the bolts on a wire wheel, and run a thread chasser in all the holes. Not a tap, they can remove metal. You only want to remove crud. Clean the pan with thinner or acetone, and the bottom of the trans too. Use 3M trim cement to glue the new gasket to the pan. Let it set and follow instructions. After its on the pan and set, soak the top of the gasket with WD 40. With a drop of WD 40 on each bolt, screw them in and tighten them only to where the gasket starts to squeeze out, no more. After a few heat cool cycles, you may give each bolt a half turn more.

08-02-2013, 06:05 PM	#4
40cpe Senior Member Join Date: May 2010 Location: Star, MS Posts: 4,024	Re: C-4 pan gasket material Sponsored Links (Register now to hide all advertisements) I was back under the car checking it this afternoon. It looks like there is one pan bolt leaking at the head and dripping on the floor. The band adjustment on the right side is wet and red but no dripping yet. I think I can seal the bolt. Can the adjuster leak be repaired externally? Necessary to drain the fluid? Thanks, Gene