8.5 Rearend Gear Interchange Issue

Hi guys. I have an older style posi with cones. I broke a couple chunks off the pinon gear and one tooth off a spider gear. It is an 8.5 . I was wondering if the parts from a non posi 8.5 would work to replace the broken gears

 

You cant mix and match pinion and ring gears. Keep them as a set. And the side gears in a posi are not the same in a non posi. They are different thicknesd

 

Send me pictures of what is broke. I might have something.

 

If it is the pinion spider gears I have a set of spiders BUT I do not have the side gears so if those are broken I can not help. Only the 2 little spiders that ride on the cross shaft.
Jim
J D

 

Thank u for the reply. I'm not sure now as to what rearend I have for sure. I thought it was an 8.5 but not sure

 

Pictures of the rear and the broken parts will help.

 

I don't know how to post pictures. Sorry

 

I do know the pinion nut is an inch and quarter and the bolts holding the ring gear r 11/16th

 

Can you email or text pictures?

 

Yes I can do both.

 

11/16 bolt HEADS? Are the bolts right hand thread or left hand thread. That will be a 8.2 rear.... 3/4" bolt head is left hand thread....is a 8.5 rear.

Pictures- Just use the UPLOAD A FILE box in the lower right of the screen and browse through your computer folders and find the picture you want and click on it and wait till it uploads ...That is it...

 

Ok sounds good. I have a rear out of a 65 lamans. Would that b the same. I not at my garage to take pictures

 

8.5" with cone style posi. That is a new one to me. Does that even exist?

 

Pontiac/BOP 8.2" is what you have.

 

I have a 71' Corp GM 8.5 with a cone style posi from a 71' Skylark under my 70' Skylark which originally sported a peg leg 12 bolt Chevy rearend from the Framingham plant. Jim

 

They did make some cone style posi units for 8.5",found mostly in 71-72 Buicks.

 

Auburn makes the cone posi units for the 8.5 still...

 

WELL IT ALL DEPENDS ON THE REAR YOU HAVE UNDER THE BUICK. you SAY IT IS A 8.5 if THAT IS TRUELY

 

AT YOU HAVE THEN no 8.5 AND 8.2 pONTIAC ARE TOTALLY DIFFERENT. iF YOU HAVE A 1967 BUICK REAR OR 1967-1972 PONTIAC REAR UNDER YOUR BUICK yes THAT WILL WORK. Crap... sorry about the caps...
The guts are interchangeable and the 65 rear WHOLE ...WILL fit the 1971 BUt there will be a few things you need to swap and or do...... And will be 1/2" narrower on each side.

WE need pictures first before guessing at all this.

Jim
J D

 

can't imagine why a person would buy a new cone style posi carrier with all the better rebuildable options out there now. I went with a Truetrac but also considered an Eaton clutch style.. An Auburn never even crossed my mind.