rcull

I have a Corperate positration carrier with 31 splines. I had thought they only had 28 or 30 splines. Could this be something exclusive to Oldsmobile?

Thanks

Fun71

Post the casting number from the carrier and someone will be able to ID what you have.

In 67-68 Olds had a heavy duty O-Type carrier with 31 spline axle shafts and a 10 bolt ring gear.

joe_padavano

What is a "corporate" carrier? Chevy 10 bolt 8.5"? Chevy 12 bolt? 7.5"?

The 8.5" Oldsmobile Type O carriers used 1966-70 came in 28 and 31 spline versions. The corporate 8.5" came in 28 and 30 spline versions. Either yours isn't a "corporate" carrier or you counted wrong or it's aftermarket. There are aftermarket carriers for the Chevy 10 bolt available with more than 30 splines.

rcull

I definitely didn't look far enough for a number, it was right under my nose
It is a common enough carrier ED32267.
It also has a 263 if that might date it?
The side gears are definitely 31 tooth.






Thanks!

joe_padavano

So this is an 8.2" carrier, not an 8.5".

rcull

OK that means I have to ask where you are supposed to measure the 8.2 or 8.5"?

The overall diameter of the ring gear is 8.5".
The retaining bolts are 7/16", 3/4" wrench.
The pinion nut is 1-1/4".
The housing has the square blocks on it.

Thanks

monzaz

That is a 8.75 or 8.875 Does the side gear have recesses for c-clips? Y/N?
Likely has 45 degree 31 spline axles which is the 1971- 1976 era
The ring gear bolt holes are for 7/16 x 20 left hand thread bolts
Cover will be a 10 bolt cover full size car rear

rcull

Thanks,
I am not sure what to think about this right now
What has someone done with this stuff to cause confusion? The cover is not original, so anything may go. The carrier has been narrowed, so could cause questions too.
No, it does not have c-clips. bolt in axles.
The 7/16" bolts were left hand threads.

The cover was not the BOP style.



How do you measure an 8.2 or 8.5 ring gear?




Thanks

rcull

Can this be an 8.2 drilled out for a 8.5 gear then installed in a 8.5 housing?

66-3X2 442

8.2 BOP posi units bolt togather,not a solid unit.

monzaz

oK SO THE PICTURE OF THE REAR END YOU ARE SHOWING IS a 8.5 1971 1972 Oldsmobile. A Body.
So you are saying that the posi unit you have was in this housing?
Need much more info here to understand what your trying to do?

monzaz

So I found this info on line.... Wallace racing.com
It looks like from a closer look at the ring gear bolt holes some one opened up the 3/8" holes to t7/16" holes... BUT the 31 spline side gears are and were never used in a 8.2 carrier SO what did they do there...Modify the side gear pockets and or the axle shaft carrier hub bearing ID to fit the 31 spline axles into the carrier case?
I HAVE SEEN many goofy things over the years...This could be one of those machinist Frankenstein units a guy just had to see if it could be done. I have learned from weird stuff like this over the years of doing rear ends...SOME stuff is neat other stuff is just plain WHY!


First Style '55-'64 - All GM cars; drop-out style 8.20" - 17 - - Early Style Standard - '64-'72 Chevelle/GTO/F-85
- '64-'72 Nova/Chevy II
- '67-'70 Camaro 8.20" 1.438" 25 2.56, 2.73 >>>>>>>>>> ED-32267 <<<<<<<<or ED-32118 3.08, 3.36, 3.55, 3.70 ED-30116 PM2 Early Style Other - '64-'71Buick/Pontiac/Oldsmobile
"B or P axles" 8.25" 1.438" 27 - - Late Style - '70-'76 Chevelle/GTO/F-85/LeMans
- '70-'76 Camaro
- '70-'75 Nova/Chevy II
- '77-'81 Z-28/Trans Am 8.50" 1.625" 30 2.41, 2.56 410409N 2.73, 3.08, 3.42, 3.73, 4.10 410408N H Car Style (light duty) - '71-'77 Vega
- '75-'77 4-cyl. Monza, Sunbird, and Astre 6.50" - - - - H Car Style (med. duty) - '75-'77 6- & 8-cyl. Monza, Sunbird, Starfire and Skyhawk 7.50" - - - - Present Style - '77-'84 All GM models except Monza, Vega and '77-'81 Trans Am's and Z-28's 7.50" 1.438" 27 2.29, 2.41, 2.56, 2.73, 2.93, 3.08 - 3.23, 3.42, 3.73 -

monzaz

found this one now too to ad MORE confusion to the works...lol.
Until we find out exactly what the casting number is 8.2 or 8.5? This will be confusion.

found on line google search
I picked up a 8.5 10 bolt out of a 71 camaro. I ran all the #s on the center section and axle tube. It is a 3.08 locking, built in 71 with an eaton posi.I started tearing it down this morning and found some of the posi clutches are in pieces so I need to replace them. I took the casting #s off the case and did a search. Its coming back as a 8.2 2 series.

The rear end currently has 3.08s and the backlash is good. It also has the larger ring gear bolts with reverse thread. The Casting # on it is ED 32267. Looking for info.

If it has 3.08s then the 3.73s I want to install should work. Can't seem to find any real info on it. HELP. I don't want to invest time and money in to it if its not going to work.

monzaz

So we know the 8.2 and the 8.5 have the same ring gear bolt pattern and ID ring gear so they can fit onto each others bodies.
BUT 8.5 is 7/16 x 20 ring gear bolts and chevy is 3/8 x 24 thread bolts
The offset could help determine the unit which makes it a 2 or 3 series unit.
8.5 ring offsets are
2 series 1 3/8" ish
3 series 1 3/4" ish
chevy 8.2 offsets are:
2 series 1 5/8"
3 series 2"
Maybe this will help to figure that unit out.
picture is difference in ring gear offset lands and how to measure.

rcull

Thanks, That probably makes it a series II. The dimension I get is about 1.722".
The axle shaft holes are about 1.345" and 1.348". Not a big difference from one side to the other, and the holes appear good but may indicate that they have been enlarged.

I had no idea I may have had a Frankenstein
If I wanted to look for 28 spline side gears is it possible to know which ones to get, or will I have to disassemble it? Not sure which way to head with it.

monzaz

It appears to be an 10 bolt 8.5 with that ring gear flange offset of 1.722 - 1.750 (1 3/4") BUT still how does it have 31 spline axle side gears...lol. Some one swapped some stuff here. LOL. I need to look at this more close. Jim

rcull

Would the 31 spline gears interchange with 28 spline? Or, would there have to be modifications made to either the gear or the casing to fit them. From previous posts the housing may have been opened up to accept the axles, but I don't see that as a problem to refitting the casing with 28 spine gears.
Thanks

monzaz

tHAT IS WHAT i AM UNSURE ABOUT. Sometimes GM will reuse dimensions on items etc. So I have done some Frankenstein stuff in the past where you just start interchanging stuff to see what fits and what does not and what you can easily modify to fit etc.

monzaz

What size race fits that carrier?
is the outer OD a 3.062 or 2.89?

rcull

I am not going to be able to answer that until Tuesday. I had to leave home to visit our new grand daughter!

rcull

It is the smaller 2.89

monzaz

Ok well for sure that was never a 31 spline unit. They had to of removed material from the ID of the bearing hub where the axle slides in.
GM had a HUGE issue with this in 1990 -1999 they were shearing off carrier bearing hubs with too much heat and load on the pick up trucks etc. when they drilled out the stock 28 spline cases and made them 30 spline. not thick enough hub to with stand the heat and stress. Aftermarket started with the conversion bearing LM102949 and LM102911 races to solve this issue and making the OD of the bearing hub larger like a 12 bolt chevy. GM did not catch up till year 2000 and then they called it a 8.625 rear....lol.
JIM
JD Race

rcull

This is a picture of the side gear in case it looks like anything to you.
If I am looking for the correct 28 spline side gear, would you have a part number that I could look for?
Thanks

monzaz

well being a EATON type unit that still should be available to buy. 8.5 28 spline Posi spider gear set. BUT if they modified the case pocket you could be doomed.
I will have to measure something I have here. Give me a day.