Thread: My Leaky Saginaw

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I have a Saginaw four speed transmission from the mid-sixties in my car and it leaks from the rear around where the driveshaft goes in like hell won't have it. I think it's the rear seal. I was wandering how big of a task it is to fix this problem. I don't care if it's jerry rigged I just want it to stop leaking.

Just replace the rear seal...Parts store should have one.

There is a bushing just behind that seal,I would suggest replacing it also.

check the yoke for worn groves in the shaft also.may need new one.

And, check the yoke for wear when you slide it out.
To be sure it's not creating extra sloppiness.

How big of a job is it to replace the rear seal and bushing?

Place a drip pan under the rear of the tailshaft housing. It won't leak a whole lot, but better to leak it into a pan than onto your working surface.
Remove the u-joint strap nuts and straps at the differential pinion. Slide the entire driveshaft forward until the front yoke bottoms out in the transmission. Swing the rear u-joint out of the way so you can pull the entire driveshaft and front yoke back and out of the tailshaft housing.

Use any appropriate tool to remove the seal. Some guys do it with an open end wrench, getting part of the wrench behind the seal and prying it out, leveraging against the end of the housing. I normally use a 3-ft long straight-slot Snap On screwdriver that my son named "Dirty Harry". to pry the seal out. All you need to do is get part of the seal out past the housing, then you can grab it with a large pair of pliers or Channellocks and yank it out. Pay attention to the orientation of the seal, which part goes to the front. If you have little experience with seals, it's easy to get them in wrong when you go back with the new piece if they're constructed with no open side, which would obviously go toward the inside. I've never replaced the seal on a Saginaw, so don't know what the seal looks like.

Going back in with the new seal, use a socket with the appropriate diameter to match up with the seal housing and tap it in gently, going North, South, East, West over and over to keep the seal square with the tailshaft housing.

Inspect the outer diameter of the yoke where it rides on the seal. If it's grooved badly, you'll likely still have an oil leak after replacing the seal. Get a new yoke. If you were doing this installation from scratch while building the car and using a yoke that was grooved, you could just pull the yoke out a little so that the seal would ride on a fresh area of the yoke and build the driveshaft length accordingly, but with your car, the driveshaft length is already established and you can't do the driveshaft length change as cheaply as you can buy a new yoke. If you encounter a nightmare trying to find a yoke (very likely), call these guys with the measurements and ask if they have one for sale or can give you a part number and source of supply....
Phone numbers are in the upper right hand corner...
http://www.drivetrain.com/contact_us/

I found this blurb about replacing the bushing on the HAMB. Interesting....
"Some of the old guys used to replace the tailshaft bushing without removing the tailshaft housing by just driving a new bushing in and forcing the old bushing into the tailshaft housing to ride forever more on the tailshaft. I don't know if your saginaw lends itself to this kind of shade tree procedure or not but it would be easy to check inside."

snap on makes a puller and installer for the bushing and seal wile the cost way too much to buy for a one time use many shops and most trans. shops have them you can just pay a few dollars to change the bushing it a vary easy job you just push the puller in its spring type fingers get behind the bush. and run it out with an air wrench and pound in a new one also some auto parts houses or tool rental places rent them. it's about a 5 min job with the correct tool.......ted