Hey y'all I've had a pretty bad trans leak for quite a while on my 83. Its an a43d automatic. I've replaced the rear output seal three times with no luck so I'm going to go ahead and replace the bushing on the output shaft/extension housing and the seal once again. My yoke has some scoring on it but I can't for the life of me track down a 79 to 83 yoke. There are a few similar ones available for later modes but the holes for the u joint cups are either too small or the shaft is longer by 3/8" of an inch.

This one is 3/8" longer than the original from the center line of the u joint to the end of the shaft:

https://www.northerndrivetrain.com/p...I-1303-41.html

Does anyone know if that would cause issues?

The original part number is 37302-30020 and appears to be discontinued.

 

Instead of trying to find a replacement yoke, why not just sleeve it to get a good smooth surface for the seal to work on? It's a stainless steel thin wall sleeve that will press fit over the damaged seal surface on the yoke. Near as I can tell this is what you need:

https://www.napaonline.com/en/p/NOS9...ndex=Universal

The NAPA link is the only one I could find online that showed the actual measurement specs, so you can check it against what specs you have on your current yoke. SKF makes tons of different sizes of these so even if this one isn't right size wise, you should be able to find the correct one. Also, you can get this for less than the inflated NAPA price, like this one:

https://www.autozone.com/drivetrain/...99147/487040_0

It's the same part made by SKF, but just has the Auto Zone "Duralast" branding/packaging. It also specifically says it's for A40D or A43D auto trans output shaft seal, so this should fit what you have.

 

There is also this: https://www.autozone.com/drivetrain/...99147/487040_0

 

Thanks for getting back, My understanding (or lack there of) is that the sleeve sits all the way down at the bottom of the yoke and is about an inch long. I figured it is meant for some of the other cars with my trans that have a much shorter yoke. My scoring is in the middle of the yoke. Would it possibly work to hammer the sleeve half way down to the point where the scoring is? I worry that would create a small lip and continue to leak?

 

The short answer is yes, it will work to only hammer the sleeve down to the point where you need the new sealing surface. The sleeve would only sit down at the bottom of the yoke if you drove it all the way down there while installing it. As I mentioned these sleeves are a press fit, which means they are held in place by friction. They are engineered to have very precise tolerances. The inside diameter of the sleeve is made just slightly smaller than the diameter of the yoke shaft, so that when the sleeve is installed, it "grips" the yoke shaft fairly tightly & will not move. That means you can drive the sleeve down to the point on the shaft where you need the new sealing surface & stop there. It should stay in place without any problems, as long as your measurements are OK. The installations instructions cover this (page 7, item 2 here): https://www.skf.com/binary/21-128020...edi-Sleeve.pdf

Item 3 in the instructions specifically indicates that you can drive the sleeve to the point when you need it, not necessarily having to drive it all the way on.

By the way, the length of the yoke shaft often has nothing to do with the type of vehicle it is in, but does have to do with expected power handling capacities, & possibly suspension travel. The yoke shaft is designed to slide in & out with up & down suspension travel. If this is a 2 wheel drive truck of a 4 whhel drive truck that isn't going to be doing any rock climbing or severe offroading (greater suspension travel while doing those), this repair should work fine. If you want to double check this, measure that "polished" area where your old seal was riding on the shaft. If it's anything less than 31/32" of an inch, or 25 mm, this sleeve will work. Those are the measurements of the depth of the sleeve's surface area (see brochure in link provided above, page 10, part # 99147).

Last item. When/if you do this, follow the instructions that come with the sleeve, don't skip any steps, & take your time doing it. Be complete & it should turn out OK.