Topic: Rear end leak
in Forum: C3 Driveline Components
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Like most things with my vetts as I fix one thing I notice something else. As I was replacing my exhaust I notice that my rear end is leaking pretty good. I am assuming its the front seal. What will it take for me to replace the seal. Would I have to drop the whole thing or can I replace it in place? Is it something a novice can do? Should I drop the whole thing and do the seal and bearings?
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On which car?
Not that it makes a lot of difference, but the '81 would be harder to do the front seal IN the car. Honestly, I wouldn't bother with replacing the seal with the diff in the car. Removing the yoke nut, and the seal can be done in car, but the problem comes when replacing the nut, and torquing it back down. If it's not done just right, the pinion bearings will usually fail rather quickly.
Before condemning the front seal, can you check a little closer and determine for sure where the leak is? 90% of the cast iron diffs will seep gear lube from everywhere...mainly the filler plug.
My opinion would be to pull the diff, and either replace the seal properly, or rebuild the complete assy.
If the leak is not so bad that it is dripping, just keep an eye on the lube level in the diff, and it should be fine for a long time....or at least until you have the time and $$$ to rebuild.
Not that it makes a lot of difference, but the '81 would be harder to do the front seal IN the car. Honestly, I wouldn't bother with replacing the seal with the diff in the car. Removing the yoke nut, and the seal can be done in car, but the problem comes when replacing the nut, and torquing it back down. If it's not done just right, the pinion bearings will usually fail rather quickly.
Before condemning the front seal, can you check a little closer and determine for sure where the leak is? 90% of the cast iron diffs will seep gear lube from everywhere...mainly the filler plug.
My opinion would be to pull the diff, and either replace the seal properly, or rebuild the complete assy.
If the leak is not so bad that it is dripping, just keep an eye on the lube level in the diff, and it should be fine for a long time....or at least until you have the time and $$$ to rebuild.
Joel Adams
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I agree with Joel. I would first clean the whole thing, and watch for where the leak starts from. Then follow Joel's advice.
Larry
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I am not sure, but I bet that David is talking about the 81. Seems like he is doing a lot of work and putting in a kot of money to that car!!
Hey yes I am talking about the 81. The 70 is in the body shop getting a new front clip that is the one getting the most money . From what I can tell the fluid is running down the the battery ground wire, the rear end scrap plate. At this point I guess I could just keep checking the fluid level. May be next fall I will tackle the rear end.
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[QUOTE=rraider1]Depends[/QUOTE]
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My 81 had a slight leak then it leaked and made noise. We had to drop the entire assembly. We replaced all seals, u-joints, rear suspension and swapped to 3:55s as long as we were there. The other stuff was a must do at that point. It was not easy.
Notice today that the rear is spreying pretty good. It does look like I will have to drop the whole thing. I just dont want to get caught in something and not have a car to drive this July
Well its picture time for the rear.
Well its picture time for the rear.in Forum: C3 Driveline Components
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