Transmission drain plug

rbullockv8

rbullockv8

Senior Member
Wondering what you guys use on a transmission drain plug to seal it. Whatever goop I used a year or two ago, the plug began leaking right away. Since I had a big pan under it, I put it off while working on other things.

Drained out the oil today. There are no visible cracks in the trans, threads are good on boss and plug, and seems to be leaking right past the threads. I don't mind some engine sweat, but don't want a 50 cent piece each day.

I've got some Permatex from my gas tank sender I can use. Or is teflon tape better? (In a web search, I see other car guys of all makes sometimes use tape).

What's your experience?

By the way, got the chassis rolling on four tires yesterday for the first time. Making steady progress. Just got to get this pesky trans leak fixed.

Thanks
 
It could be the rear of the transmission leaking down to the drain plug and making it look as if the plug is leaking. There are two shafts at the rear of the transmission that are very prone to seeping fluid leaking out
 
Nope. The trans case is dry. It's still a non-driving car and hasn't moved from the garage. But I'll keep an eye on those rear seals when I get it going. Good thought.
 
Try some teflon tape wrapped clockwise on the plug and don't be afraid to snug it down. See if that helps.
 
Terry said:
It could be the rear of the transmission leaking down to the drain plug and making it look as if the plug is leaking. There are two shafts at the rear of the transmission that are very prone to seeping fluid leaking out
Click to expand...

My thoughts the same as Terry . But try Permatex non hardening ..
 
Terry said:
It could be the rear of the transmission leaking down to the drain plug and making it look as if the plug is leaking. There are two shafts at the rear of the transmission that are very prone to seeping fluid leaking out
Click to expand...

Terry,OH, I apologize. I think you might be right. I got a better work light under there to tighten the wishbone cap and put in the cotter pins, and I saw a slight reflection of a very thin line of trans oil trailing down the back slope of the trans case. Couldn't see it before. I will hope that seals with some revolutions, but if not, I might be trying some of that BlueDevil product. Sure don't want to pull this whole thing apart. So much for a professional rebuild. Hope the rest of the trans innards hold up. :-)
 
I always use a product called Green Stuff, made by jomar.
Works on fuel oil and coolant fittings, it dries, but never gets hard and brittle.
Used it for many years, should be avail from any pipe supply.
 
Maybe to help fill in your blanks....:eek: Order Mac Van Pelts "In's and Out's of Early Ford Transmissions" pretty sure you had a "professional rebuild", these 3 speeds leak @ the rear shaft areas.

In Mac's "In's and Out's" page 52 General notes clearly talks about and explains your/our issue which Terry noted in his reply and Mac talks about specifically in the general notes third paragraph, "prone to seepage" @ the 7140 Idler and 7111 counter shafts.

Now I remember a web site that did have replacement Idler/counter shafts with "O" rings that did help with this condition and may involve a re-bush @ the case openings if it's a few thousandths larger than the shaft but your not alone with the drips brother...we all got'um:D. Scott
 
If I use anything at all on those transmission/banjo rear drain plugs, and most times I don't, it would be 3-4 wraps of Teflon tape and snug those plugs down good. However, I would never use Teflon tape on any areas of the engine oil system or any gas line connections where little pieces of Teflon could windup plugging oil or gas flow. Probably more info than you asked for or needed, but I'm just sayin'.
 
There was a recent post here, i think, describing how someone came up with a good and unique way to plug the ends of those counter shafts, and locking pin holes, to stop that leak which normally occures at the rear of these early Ford 3 speed transmission cases. Don't recall exactly when, or on which thread I saw that. I'm sure someone good at remembering things, like DD, or someone good at doing searches, like DD again, could find this.
 
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There are no seals on the shafts. When I rebuild I use new shafts with O-rings on the shafts. Try some of the ideas above to seal them.
 
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