Classic/Antique Car Repair: 1969 C4 Transmission Rear shaft seal, splined shaft, shaft seal

Question
QUESTION: Hi and thank you in advance for any information. I am need to replace the Yoke Seal on my 1969 Mustang which has a 302 C4 combination. I am looking for advice on how to remove the old seal. During my initial inspection it doesn't look obvious to me how to get it separated from the end of the transmission and I want to be careful about damage. Any suggestions would be very helpful.

Thank you in advance,
Mike

ANSWER: The seal is pressed in, and it takes a seal removing tool to pull it out.  You may be able to rent one from a rental place - it looks like a very sturdy metal cup, with a hollow, tapered, threaded, center part that screws into the inner lip of the old seal, and when the rear bolt on the tool is screwed tight, it slowly threads into and grabs and pulls the old seal out.  

If the seal was installed using any adhesive, it might be very difficult to get out - and some shops do that, although it isn't really neccesary (they don't care about the next guy!)  

Of course you have to remove the companion flange first, by taking out the center nut, and then sliding the flange off the output shaft so there will be room for the seal puller.

If all this seems like too much, you can take the car to a transmission repair place and get them to do it for you - since they have the tools and experience, it should be pretty cheap.  Don't go to a chain store, go to a locally owned shop with an old curmudgeonly mechanic with grease under his fingernail - he will know what to do!

Dick (I think I just described myself!)

---------- FOLLOW-UP ----------

QUESTION: First Thank you very much for your fast reply and info.
I feel pretty comfortable working on this myself especially since the car is not registered so its hard for me to go to a shop. Can you clarify for me what you meant by a companion flange? I removed the drive-shaft and Yoke and replace the U-Joints. What I see is the end of the transmission with the seal and a splined shaft that sticks out slightly from  the transmission. There seems to be plenty of room around the seal. I have already purchased a new seal. I do not think there is any epoxy as I suspect the seal is still the original one.  What is the correct name for the tool that I can look for as you suggested? Is is a trans shaft seal removal tool?

Thank you again.
Mike  

Answer
Ok, Mike you're on the right track here.  The "companion flange" is the part you've sucessfully removed- that is the name for the part that you slid off the rear shaft of the transmission; it's the part that couples to the front U-joint.

Once that is out of the way, yes, there is a gap between the seal lip and the transmission shaft - that is where the tool wedges itself in, to grab the seal and extract it.

Since you already have the companion flange out, inspect the surface on which the seal lip rides - there will be some wear there.  This is what causes a leak - if the wear is severe, you may have to position the new seal either further into the housing, or not as far in, so that the seal lip rides in a different place on the companion flange.  The other way to be sure you'll get a good seal is to purchase a new companion flange - they may be easy to find at a Ford parts place - I don't know for sure.

The name of the tool you need is a "Transmission rear seal removing tool" - you can go to a tranmission shop and ask them to show you one, or perhaps even borrow one from them - if they are nice folks.

Dick