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#30963 05/01/2004 8:04 PM | Joined: Nov 2003 Posts: 19 Junior Member | | Junior Member Joined: Nov 2003 Posts: 19 | I had my 66 c20 parked in the driveway for a couple days and just noticed a new leak between the drive shaft and the rear end. The driveway is on a slight slant so it seems to be coming from the rear end. I assume there is a seal that need to be replaced. Is this the correct fix and if so,
how difficult a job is it. Any help would be appreciated. | | |
#30964 05/01/2004 9:31 PM | Joined: Feb 2001 Posts: 1,897 Member | | Member Joined: Feb 2001 Posts: 1,897 | Someone here says it is not leaking,,, it is only marking its territory!  How close is it to the rear axle?
There is enough good in the worst of us and enough bad in the best of us that it does not behoove any of us to criticize the rest of us.
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Be yourself. If you are ever lost, It will be much easier to find yourself if you know who you are!
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#30965 05/02/2004 1:01 AM | Joined: Feb 2004 Posts: 29,749 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,749 | Replacing a pinion seal is no big deal, IF you get the flange nut torqued right after the seal is installed. There should be a little bit of bearing preload when the job is done, a drag as the pinion is turned. I usually check the load with an inch-pound torque wrench before disassembly, and try to dupilcate it when I retighten the pinion nut after installing the new seal. If there's NO drag, it probably means you've got a bearing in the process of failing, and it needs to be replaced or the seal job won't last long. That gets into some definitely precision setup, as the pinion gear has to be removed, both bearings replaced, and the preload has to be set from scratch. If there's any front-to-back movement of the pinion flange, you're in for a bearing replacement, not just a seal. Take the job to a pro with the right equipment in that case!
Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!
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#30966 05/02/2004 6:55 PM | Joined: Nov 2003 Posts: 19 Junior Member | | Junior Member Joined: Nov 2003 Posts: 19 | The leak is right at where the end of the driveshaft goes into the differential. | | |
#30967 05/03/2004 3:16 PM | Joined: Nov 2003 Posts: 19 Junior Member | | Junior Member Joined: Nov 2003 Posts: 19 | Hey guys, thanks for the input. Before I start replacing the pinion seal, I read that if the vent is clogged, it will cause the oil to leak.
I figure I should see if that's the case before I
do the tougher stuff. Where is the vent on the 3/4
ton rear end? I was under there briefly last night and couldn't find it. It must be on top, right? And what does it consist of or look like. | | |
#30968 05/03/2004 4:47 PM | Joined: Feb 2004 Posts: 29,749 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,749 | The vent is usually part of the bolt that holds the brake line tee fitting in place. Follow the brake flex line from the frame to the rear end, and you'll either find a loose-fitting metal cap on top of the bolt that holds the brake line tee on, or a rubber hose attached to the top of the bolt that ends up somewhere inside the frame.This allows for air expansion inside the rear end housing. (Lets water in, too, if you submerge the rear end!)
Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!
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#30969 05/03/2004 6:50 PM | Joined: Feb 2001 Posts: 1,897 Member | | Member Joined: Feb 2001 Posts: 1,897 | There or look at the top of the axle tube for a small nub that has a slightly loose cap on it. Some will have a hose from the axle to the frame with the nub (also known as a breather or vent) at the end of the hose.
There is enough good in the worst of us and enough bad in the best of us that it does not behoove any of us to criticize the rest of us.
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Be yourself. If you are ever lost, It will be much easier to find yourself if you know who you are!
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