Rear Main Oil Seal

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Larryjb

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Here is a pdf version of my procedure. I have removed the unnecessary steps.

Yes, Mark, I have included removing the axle-diff bolts, but I'm not completely removing the differential. This step takes less than 10 minutes and saves a lot of !@#$%-eh's. If anyone wants to know, I understand that removing the center link/pitman arm bolt allows the center link to rotate away from the differential so that it could be removed completely.

If you see any mistakes, let me know so I can correct them.

Updated to include list of tools needed. Get them ready, job goes faster, more time for beer after.
 

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Rocket Man

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Here is a pdf version of my procedure. I have removed the unnecessary steps.

Yes, Mark, I have included removing the axle-diff bolts, but I'm not completely removing the differential. This step takes less than 10 minutes and saves a lot of !@#$%-eh's. If anyone wants to know, I understand that removing the center link/pitman arm bolt allows the center link to rotate away from the differential so that it could be removed completely.
Don’t you have to drain the diff if you pull the axles? I’m not saying any one way is best and don’t mean to beat that subject to death but all I needed to do was pull the bolts that hold the diff to the frame, pry down on it one time and it stayed , and remove the pan. That’s how all the guys I saw on YouTube do it and it worked great. If it doesn’t stay down you can place a wooden wedge in there to hold it down. It doesn’t strain the CV joints any more than if you lifted the suspension, and it’s not being driven while it’s in that position. Just a FYI to anybody doing this. Or do it the other way, it’s up to the person doing the work. I say weigh your options and choose what you think is best. I had no problem cleaning the gasket surface, pulling or replacing the pan. Thanks for your work with that PDF Larry, that’s very considerate of you.
 
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Larryjb

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Don’t you have to drain the diff if you pull the axles? I’m not saying any one way is best and don’t mean to beat that subject to death but all I needed to do was pull the bolts that hold the diff to the frame, pry down on it one time and it stayed , and remove the pan. That’s how all the guys I saw on YouTube do it and it worked great. If it doesn’t stay down you can place a wooden wedge in there to hold it down. It doesn’t strain the CV joints any more than if you lifted the suspension, and it’s not being driven while it’s in that position. Just a FYI to anybody doing this. Or do it the other way, it’s up to the person doing the work. I say weigh your options and choose what you think is best. I had no problem cleaning the gasket surface, pulling or replacing the pan. Thanks for your work with that PDF Larry, that’s very considerate of you.

I'm not actually pulling axles, rather I'm separating the outer axles from the inner axles. GM actually calls the front differential the "inner axle". There is another set of bolts securing the inner axle to the differential carrier. If you unbolt the inner axle from the differential carrier, yes you would have to drain the differential fluid for sure.
 

Rocket Man

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I see. It’s weird that mine came down fine without pulling those. It needed to be pried down but when I did that it seemed to stay. Hopefully I never need to do it again but if I do I’ll keep that in mind.
 
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Mine might have come down easily too, but when I saw how much Rickafix had to reef on his I decided it would be easier to just undo 12 more bolts and let it drop.
 

wildcatgoal

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Replaced oil pan gasket without removing diff, disconnecting front differential, disconnecting axles... just unbolt it, lower it, pry it, remove pan, go in reverse. PITA but job done. Get the Mahle gasket -- only one that the main structure is one piece.
 
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Replaced oil pan gasket without removing diff, disconnecting front differential, disconnecting axles... just unbolt it, lower it, pry it, remove pan, go in reverse. PITA but job done. Get the Mahle gasket -- only one that the main structure is one piece.

Nick, sure, it can be done this way.

The only thing I did differently from you is to have separated the outer axles from the inner axles, 12 easy bolts.

"without removing diff, disconnecting front differential, disconnecting axles..." This sounds like a lot of work. I didn't do this:

-I did not remove the differential, just lowered like you did.
-I did not disconnect the front differential, at least not from the inner axles.
-I did disconnect the outer axles from the inner axles.

Yes, it can be done your way, and as you said, it can be a PITA. 10 extra minutes to disconnect the outer axles and the differential drops down out of the way and takes care of the PITA. Actually, because I work slowly, it would probably take anyone else 3 minutes to disconnect the axles. It's that easy to do.

To each his own. I'm just suggesting an extra step that some might prefer.
 

OR VietVet

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I think the old phrase that comes to mind is, "Work smart not hard". I personally would disconnect the outer axles in that short amount of time it takes to do it. I have seen attempted short cuts come back and bite a tech in the ass, creating a comeback.
 

Rocket Man

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I’m pretty sure he meant the job as a whole is a PIA. This has been beaten to death. Pull those bolts, don’t pull those bolts. It’s not a big deal either way. The job is still a PIA. Not anywhere near as much as the rear main, but it’s a PIA. Anything you have to do under the truck is. I had no problem without pulling the axles apart, I haven’t tried it with doing it and Larry didn’t try it without doing it. Everybody made their point. Time to let it rest. Sheesh.
 

OR VietVet

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Sheesh is right. I didn't mean to interject my opinions when you were controlling all abject thoughts on this matter. I bow to your knowledge.

Nevermind. I take this back. Not gonna stoop no more.
 
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