factory 8.5 posi id at the u-pull-it

[Blazer406]

ran across this on buickperformance.com

Thought some of you junkyard scavengers (like myself) looking to save a buck might find this of some use....

posi article

I was looking for info on the 30 spline eaton clutch type posi.... what exact models it came in....etc....

Anyway.... maybe someone here can find some use in this article.

Enjoy.

 

[novaderrik]

i don't think GM put any 30 spline Eaton posi's in anything. when they switched to the 30 splines in the early 90's, they went to the Auburn cone style and the craptastic lockers they put in the 1/2 ton pickups.
but a 28 spline Eaton posi should be relatively easy to find- any 71 to late 80's 8.5 with a posi had the unit we need, but you have to be careful that you get one from a vehicle with 3.08 and numerically higher gears. and if the clutches are worn, you can get them new from GM.
i paid $125 for a rebuilt Eaton posi out of a late 70's Z/28 that came with a set of used 3.70 Richmond gears for my Nova back in 2000.

 

[Blazer406]

I was told the b-bodies in the 90's had the clutch type rebuildable posi....and 30 spline axles..... not sure what else.....

Are you saying these had Auburn's?

EDIT: After searching over at impalassforum.com .... they are whining and complaining about the stock Auburn cone type posi.....most change it to the Eaton rebuildable unit when they change their gears out....

One note.... their cars weigh 4400 lbs.... and still use the 8.5 rears.... these are some stout units.... I realize most Impy's rarely see the kind of torque a near stock Buick V6 can inflict on big boost.... but still..... 4400 lbs... yikes....

 

[turbofish38]

I was told the b-bodies in the 90's had the clutch type rebuildable posi....and 30 spline axles..... not sure what else.....

Are you saying these had Auburn's?

EDIT: After searching over at impalassforum.com .... they are whining and complaining about the stock Auburn cone type posi.....most change it to the Eaton rebuildable unit when they change their gears out....

One note.... their cars weigh 4400 lbs.... and still use the 8.5 rears.... these are some stout units.... I realize most Impy's rarely see the kind of torque a near stock Buick V6 can inflict on big boost.... but still..... 4400 lbs... yikes....

Yep. I'll ditto what Derrik said. I've sold a few of those 30 spline Auburns to some TR folks. I haven't heard of anybody fragging one. 1989 and newer B-body is 30 spline. I find it hard to find a posi,especially an Eaton since I'm not in the snow belt. Good thing most cop cars had it.

BTW the guy in your link is a dork. If you position the carrier with the opening facing down and shake the axle shaft back and forth the C-clip will fall out into the diff housing. I made a tool to remove the yoke. I took a 30" long piece of channel steel bar. I drilled two holes in it to match the mounting holes of one U-joint strap. With one hand on the tool and the other on the breaker bar busting the nut loose is a cinch.