D 20 advice

[drinkin_buddy]

Ok, I've got questions, really basic questions.....

I am attempting to reseal my Dana 20 and have an issue. Seems that someone in their infinite wisdom, decided to use some sort of gasket sealer on the rear output assembly. I have beat this thing with every non marring tool I have in the garage and it still will not budge! I am very reluctant to use any sort of prying tool on the gasket surfaces to pry them apart, but I am running out of ideas.


Also, can someone tell me the proper distance to sink the new yoke seals? I could be wrong, but I do not see a positive stop for the new seals, and I know I have to sink them a certain amount to clear the little metal felt seal retainer that sits on the bottom of the yoke. Or..... Can I use that retainer to May advantage by putting the yoke on and torquing down the nut to push my new seal to its proper depth???

I know, trivial questions, but I only want to pull this heavy sob one time.....

 

[Michael Mayben]

Common issues seen on these units when someone else has previously butched 'em!

As for separating the output assembly (it most likely will have at least one, maybe more) shims between the flange and the case), I use a high quality putty knife (not cheezee chinee crap) that I have carefully sharpened on a belt grinder to a knife-like edge.

I know what all the references and "tech" sez about doing this, but then they are working with new units on a clean system, in a factory "shop" where conditions are perfect, and no po has scruud everything up!

Carefully "tap" (as with a light hammer) the tip of the putty knife into the joint, work around it at several points. You want to "wedge" the bond (someone has no doubt used fukkin' rtv on it) between the housing flange and the case where the shims are. You May actually damage a shim since some of 'em are kinda like foil, but that is the cost of doing bizznizz. Once the adhesive "bond" is broken, then the housing should pull right on off as an assembly.

Doing this will not damage the case or the housing if done with some finesse.

The replaceable seal gets driven in flush with the top of the counterbore, when the damaged seal is removed, the counterbore will be apparent. Do not attempt to "pull" or "press" a seal in using the slinger on the yoke. Some yokes don't have a slinger incorporated anyway.

When the yoke is in your hand, you will see a deep "groove" worn in it's sealing surface from riding on the old seal with embedded grit. You must deal with that in some fashion or the new seal/yoke will leak just like before. Two ways to do this...

The expensive way, install a "speedee-sleeve" repair bushing over the damaged yoke surface. The other expensive way...replace that yoke with a new one!

The cheepo/redneck way that I use....find some sort of "shim" that will slide over the output shaft spline and seat against the inner bearing race. Needs to be at least 0.050" in thickness and can be as much as 1/8". Then when the yoke with the groove is re-installed, the seal will ride onna virgin surface and seal up the yoke as new!

The shims I use for doing this are actually the same shims included in the overhaul kits for setting output shaft/bearing preload on the opposite side of the bearing!!! This is a workaround for being able to re-use a damaged yoke and this procedure is not covered in any service manual. We do this same workaround on drive axle pinion seals and same for transmission outputs that have bolt-on yokes.

 

[drinkin_buddy]

Thanks for the advice Mike, I will try a putty knife tonight when I get home.

I've already got the old seals pulled. By the way, they were a major pain. If I knew that they would put up such a fight, I would have pulled them with the case still bolted to the trans.

Anyway..... I dont remember seeing a counter bore inside the seal area. It was sort of dark and if it is a slight taper, I could have missed it.

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[Michael Mayben]

thanks for the advice Mike, I will try a putty knife tonight when I get home.

I've already got the old seals pulled. By the way, they were a major pain. If I knew that they would put up such a fight, I would have pulled them with the case still bolted to the trans.

Anyway..... I dont remember seeing a counter bore inside the seal area. It was sort of dark and if it is a slight taper, I could have missed it.

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Of the two complete d20 units I have on the ground, and three rear output shaft housings I have on the shelf, a total of three parts have a seal counterbore and two do not. That's just a design change and means nothing! There is always going to be a chamfer on the entrance side to aid in seal insertion, but no taper for anything else, only a counterbore for the seal seat if used.

If you were installing the seal using a proper "driver", the flange on the driver arbor would prevent the seal from going in too deep.

With any similar housing with no definite counterbore, simply knocking the seal in a bit deeper will relocate the lip on the yoke surface and would also enhance the setup as that allows the lip to ride the clean surface.

 

[drinkin_buddy]

I will try just knocking it in square and deep enough to where the felt and slinger are inside the bore.

That felt does not need to touch the face of that seal or anything, does it?

One more question..... Is there a source for the oring type seal that seals the yoke to the splines? Mine look a little rough and they were not included in the crown seal kit

 

[Michael Mayben]

I will try just knocking it in square and deep enough to where the felt and slinger are inside the bore.

That felt does not need to touch the face of that seal or anything, does it?

One more question..... Is there a source for the oring type seal that seals the yoke to the splines? Mine look a little rough and they were not included in the crown seal kit

As for the "o" ring spline seal, I think you refer to the splined rubber washer that goes onto the spline after the yoke is installed and before the washer under the nut goes on?? If so, I've never seen those available separately though I do have quite a few. I don't use those myself.

Instead...after the yoke is completely seated on it's spline and hard against the inner bearing race, I apply a very thin bead of "grey" or "black" permatex "right stuff", that would be product number 34311. The spline and yoke must be clean and dry. Then mount the washer, nut, and torque it. Do not use any other form of "silicone", and any rtv product is worse than nothing!

I've found over the years that using the rubber splined washer that was oem from spicer is no better than using nothing as far as oil migration past the splines is concerned.