I'm now getting far enough along in my various repairs that oil leaks are starting to annoy me. The most annoying is the transmission leaks as this falls right on the exhaust and smokes a ton. Gives my neighbors something to laugh at, but this isn't a good enough reason to leave it.

I've isolated three leaks; two of which I think that I can deal with this weekend.

The first leak is in the fitting that connects the speedo cable tthe tranny. I think that i need to remove the cross member to really get at this which brings up my first two questions.
1) Does the tranny have to be supported when removing the cross member? I assume yes
2) Does the exhaust have to come off to get the cross member off? I hope no.

The second leak is in the tranny tail shaft. I have to remove the drive shaft to get at this one. One of my service manuals says that part of the differential needs to come off to get the drive shaft off. This seems crazy but brings up questions 3:
3) Does any piece of the differential besides the u-joint straps have to come off on an '81 to remove the drive shaft?

The last an ugliest of the leaks is from somewhere under the bell housing. i haven't even pulled the cover off in fear of what I will find. Assuming that it is in the front tranny seal and not the torque converter itself:
4) Can the front (input shaft) seal be replaced without removing the tranny?

As always, your help is appreciated.

 

If it were me and I had this combination of leaks from the transmission, I'd pull it and rebuild it.

The speedo cable input connector should be easy enough. The rear main seal... ah I dunno I'd want to deal with trying to square it off during installation underneath the car... the slightest twist or angle and that thing will leak right away. As for the input shaft, you won't be able to take care of the front main seal without removing the tranny as far as I know.

best of luck, if you have the time and resources, bite the bullet and set her up on jackstands for a week while you take care of her various leaks.

cheers

the blonde weasel

 

Same problems on my '81.

The tranny does indeed need to be supported to get the cross-member off. After that, you can hang it low but be very careful of what might break under the hood: distributor pushed into the firewall, fan blade puncturing the radiator, etc. Really no reason to drop it that far, though.

The output shaft seal is easily replaced by pulling the driveshaft; no need to mess with the diffy, all nuts are easily reached. However, it's very easy to ruin the new seal during the tap-in process (don't ask me how I know). A very large socket helps, but if you've never done this before, count on a return trip to Auto-zone for another seal.

Also check the two cooler lines on the passenger side where they connect to the tranny, as well as the cable near there.

The only way to replace the front seal is to separate the engine from the tranny, and I doubt that you can pull the tranny without the engine...

 

I hate to mention this but the leak at the bell housing could be your rear main engine seal. I would, at least, check to make sure it wasn't leaking there too. If it is, I would pull the tranny and reseal it and replace the rear engine seal too. I hope your repairs are minimal.
Bernie

 

While the rear main may be leaking as well, the major flow is pink.

I think that eventually I will have replaced every piece of rubber in this car.

 

I do feelv your pain or frustration. My '79 hadn't been touched in 27 years so every piece of rubber is having to be replaced. The end result will be be a very reliable, dry, fun to drive car. Good luck with your repairs and don't let it get the best of you.
Bernie

 

I spent some time this weekend looking at the various leaks and the amount of work it would take.

I came to the conclusion that the output shaft appears to leak the least. I also came to the conclusion that every seal in the tranny is leaking.

I chickened out and decided to take Bernies advice. I'm going to continue parking it over a drip pan for the time being and this fall, when I plan to pull the engine, I'll send the tranny out for a rebuild (and reseal) at the same time.

 

One thing you could try is a different fluid.
Various fluid types have an effect on the "swell" of the rubber seal.
For example, a Buna N rubber seal will swell the following with
these fluids: TypeF (-0.51%) DexronII (+2.5%) B+M Trickshift (+3.8%).
Also, you could try a "stop leak" additive. This basically will cause
the rubber to swell and (hopefully) tighten up the rubber seals.
It's not the right way to fix it, but it might get you through the
summer with less smoke and puddles.

 

Interesting idea NH. I hadn't really thought about that but you're right. it may get me through he summer. I'll be rebuilding in the fall in any case. Funny thing is, I checked around and the difference between a full tranny rebuild and just replacing all of the seals is around $100. Just parts too as the labour is identical for either.