8.5 axle bearing ??

[85GPLef41]

Well... last year i scored two 8.5 rear diffs. One is from a 85 442 open diff with 3.42 gears and the other is one from a 87 GN 3.73 posi with 3.73 gears. I am going to start my GP's rebuild and plan on using either rear diff. I started to inspect them and noticed that the axle bearings on the GN unit stuck out farther then the "stock" 442 rear diff... The 442 rear was pulled from the car that was rear-ended and stripped and jacked up beyond belief! The GN unit was pulled from drag racing Monte with Hotckis upper and lower control arms and those rear braces and it was pretty easy to identify by this and was confirmed by the stamping numbers:

now both rear diffs look ok but the bearings are what confused me. I pulled the diff covers and they both seem to be in good shape and nothing is visibly different but the axle bearing difference is somewhat a issue.. Here are the pics and if anybody could help it's greatly appreciated..
"87 diff"

"85 diff"

 

[Peter]

those are not axle bearing, those are axle seals, that issue is not a big deal. remove the axles and removed those two axle seals (prying with a flathead usually works) and install new axle seals which can be had at any parts store then reinstall the axles

 

[pontiacgp]

That is a bearing and it's called an axle saver bearing. It's used when a groove is made in the axle from the original bearing and what an axle bearing saver does is place the bearing on a different section of the axle further out from the position of an OEM bearing. The axle seal is incorporated into the axle bearing saver

 

[GhettoRacingKid]

That is a bearing and it's called an axle saver bearing. It's used when a groove is made in the axle from the original bearing and what an axle bearing saver does is place the bearing on a different section of the axle further out from the position of an OEM bearing. The axle seal is incorporated into the axle bearing saver

good info pontiac.

I would say the best thing axels from the other rear and replace the bearing.

 

[pontiacgp]

Before you go hunting down other axles check these ones out if you don't want to run with these bearings, the axles may be alright. Some guys will use the axle saver bearings thinking with the bearing sitting further out there is less flex on the axle from the wheel and less chance of the axle breaking

 

[Peter]

ok i guess i was wrong, never heard of axle saver bearings

 

[85GPLef41]

Before you go hunting down other axles check these ones out if you don't want to run with these bearings, the axles may be alright. Some guys will use the axle saver bearings thinking with the bearing sitting further out there is less flex on the axle from the wheel and less chance of the axle breaking

Thanks Pontiacgp! forgot all about those type of bearings... 😳 When i rebuild the rear i will go through and make sure that the axles are in good shape.May be a excuse to upgrade to some aftermarket 30 spline with matching posi. 😀

 

[pontiacgp]

ok i guess i was wrong, never heard of axle saver bearings

many people havn't heard of them and most would rather change the axle...the only reason I know about stuff like this is building and working on race cars for year

.May be a excuse to upgrade to some aftermarket 30 spline with matching posi. 😀

the 8.5 came with the 28 spline and there are 9 sec grand nationals out there using the 28 spline axles....I think you have to move up to a 12 bolt to find a 30 spline

 

[TexasT]

ok i guess i was wrong, never heard of axle saver bearings

many people havn't heard of them and most would rather change the axle...the only reason I know about stuff like this is building and working on race cars for year

.May be a excuse to upgrade to some aftermarket 30 spline with matching posi. 😀

the 8.5 came with the 28 spline and there are 9 sec grand nationals out there using the 28 spline axles....I think you have to move up to a 12 bolt to find a 30 spline

28 0r 30 spline for an 8.5 10 bolt. The newer truck, and ss impala, etc are 30 spline. Beware of the gov lock posi. They are grenade prone when spun too fast and lock up. Bang goes the carrier.

Eaton is good stuff and I have heard good things about the Yukon copy, though I have no personal experience.

 

[85GPLef41]

28 0r 30 spline for an 8.5 10 bolt. The newer truck, and ss impala, etc are 30 spline. Beware of the gov lock posi. They are grenade prone when spun too fast and lock up. Bang goes the carrier.

Eaton is good stuff and I have heard good things about the Yukon copy, though I have no personal experience.[/quote]


That's what i thought.. I had read about getting a 30 spline Truetrac with 30 spline GN axles...