Author Topic: 8-3/4 Axle Inner Oil Seals  (Read 4650 times)

Offline GCC

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8-3/4 Axle Inner Oil Seals
« on: May 10, 2015 - 06:45:32 PM »
I have a '70 Barracuda with an 8-3/4 rear axle and am replacing the axle inner oil seals (among other things).  Looks like the seals that came out were original, with the mopar pentastar, and numbers 2881185 & 63534.  These seals appear to have a small raised taper of rubber on the outer diameter.  Most of the aftermarket seals I have found don't have this feature; is that anything to worry about?  See pics




Offline 734406pk

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Re: 8-3/4 Axle Inner Oil Seals
« Reply #1 on: May 10, 2015 - 07:33:43 PM »
The new style seals should work just fine. Make sure to drive them in so the outside is flush with the housing. The old style had a stop on it.
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Offline msbaugh

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Re: 8-3/4 Axle Inner Oil Seals
« Reply #2 on: May 10, 2015 - 07:51:10 PM »
Also on the new seal there is a little rubber band like elastic piece around the inside diameter of the seal. This is where the axle slips through and it holds it tight. Be careful when the axle shaft slides through as knocking it off could lead to an eventual axle leak. 

I know from a long lived frustration I had, trust me.

I like getting a pvc pipe with the same OD as the seal, bang on it and it's a cheap/fool proof seal driver that helps get it in straight

Offline anlauto

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Re: 8-3/4 Axle Inner Oil Seals
« Reply #3 on: May 10, 2015 - 08:09:58 PM »
Grease up the new seals good before installing them....never install dry :2cents:
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Offline GCC

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Re: 8-3/4 Axle Inner Oil Seals
« Reply #4 on: May 10, 2015 - 08:58:50 PM »
Thanks everyone; greatly appreciated!!   :ylsuper:   :cheers:

Offline 734406pk

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Re: 8-3/4 Axle Inner Oil Seals
« Reply #5 on: May 11, 2015 - 10:37:54 PM »
Thanks everyone; greatly appreciated!!   :ylsuper:   :cheers:

Best of luck with your project!
1973 Challenger 440 6 pack auto 3.91 rear
2012 Dodge Ram 3500 dually 6.7 Cummins Fleece EFI Live
1973 Challenger 318 2bbl auto 2.73 rear 22.5 mpg RIP
1970 Challenger TA 340 4bbl auto-Sold and sad
1999 Dodge Ram 3500 dually 5.9 Cummins Fleece tuned VGT-sold
1995 Kawasaki ZX1100E & still alive

Offline GCC

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Re: 8-3/4 Axle Inner Oil Seals
« Reply #6 on: May 12, 2015 - 06:55:31 PM »
How about on this gasket, between the axle flange and the brake plate?  How are these designed to seal?  Any sealer required?  Is the material steel?  Thanks-

Offline msbaugh

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Re: 8-3/4 Axle Inner Oil Seals
« Reply #7 on: May 12, 2015 - 07:33:35 PM »
How about on this gasket, between the axle flange and the brake plate?  How are these designed to seal?  Any sealer required?  Is the material steel?  Thanks-

I put a small amount of gasket maker on mine just because I was fighting a stubborn leak. Been a couple years now no issues

Offline 1 Wild R/T

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Re: 8-3/4 Axle Inner Oil Seals
« Reply #8 on: May 12, 2015 - 07:56:07 PM »
The new style seals should work just fine. Make sure to drive them in so the outside is flush with the housing. The old style had a stop on it.

If you stop when the outside is flush with the housing the axle won't go in all the way... The bearing lock collar will hit the seal.....   If you look in the axle housing there is a machined bore that stops & from there the housing isn't machined... The seal seats against that step.....

Oh and about this

Also on the new seal there is a little rubber band like elastic piece around the inside diameter of the seal. This is where the axle slips through and it holds it tight. Be careful when the axle shaft slides through as knocking it off could lead to an eventual axle leak.

That rubber band is actually normally a spring called a garter spring... It can easily be dislodged from it's proper location when driving the seal in.... The easy way to prevent this from happening is to fill the groove on the back of the seal where the garter spring lives completely full of grease...
« Last Edit: May 12, 2015 - 08:05:57 PM by 1 Wild R/T »
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Offline anlauto

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Re: 8-3/4 Axle Inner Oil Seals
« Reply #9 on: May 12, 2015 - 08:05:13 PM »
The metal axle flange gasket is a squeeze fit...you shouldn't need a sealer if the surfaces are clean and true.

I agree on the inner axle seal...it goes a couple of inches into the tube. :2cents:
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Offline msbaugh

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Re: 8-3/4 Axle Inner Oil Seals
« Reply #10 on: May 12, 2015 - 09:34:17 PM »
Good clarification! I had no idea what the actual name of that was. Rubber band was only description I could think of at the time

Offline 734406pk

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Re: 8-3/4 Axle Inner Oil Seals
« Reply #11 on: May 12, 2015 - 10:09:34 PM »
If you stop when the outside is flush with the housing the axle won't go in all the way... The bearing lock collar will hit the seal.....   If you look in the axle housing there is a machined bore that stops & from there the housing isn't machined... The seal seats against that step.....

Oh and about this

Also on the new seal there is a little rubber band like elastic piece around the inside diameter of the seal. This is where the axle slips through and it holds it tight. Be careful when the axle shaft slides through as knocking it off could lead to an eventual axle leak.

That rubber band is actually normally a spring called a garter spring... It can easily be dislodged from it's proper location when driving the seal in.... The easy way to prevent this from happening is to fill the groove on the back of the seal where the garter spring lives completely full of grease...

Yes you are correct. The INNER seal goes to the stop. I was thinking of a different axle like a Ford 8.8? The garder spring is easy to dislocate from the seal. Be very careful inserting the axel as to not dislodge it. You can make an  extension tool to support the axle while you pass it thru the seal. It's helpful.  Just catch a few wheel studs and extend with a pipe or tube. Just like a cam tool. This can save you from a leaky axle and a do over. Good luck!
1973 Challenger 440 6 pack auto 3.91 rear
2012 Dodge Ram 3500 dually 6.7 Cummins Fleece EFI Live
1973 Challenger 318 2bbl auto 2.73 rear 22.5 mpg RIP
1970 Challenger TA 340 4bbl auto-Sold and sad
1999 Dodge Ram 3500 dually 5.9 Cummins Fleece tuned VGT-sold
1995 Kawasaki ZX1100E & still alive