When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
I had to make new topic about my rear to clear things for me.
To give all necessary info for starters, my car is '76 Cutlass S with option W29- 442 package, and build in Arlington, TX. 350+350.
Well, today i disassembled my rear. What i found left me with just questions.
I have bolt-in axles. I was simply assuming i have C-clips from everything i found.
Well, my 76' Service Manual indeed tells me this is " type O or B 8 1/2" axle, and probably was even available at 76' since my service manual mentions about it and have 1/3rd of page ( from memory) about it.
Axles are 28-spline, yoke uses two straps and bolts, bolt-cover has 10 bolts.
Diff.cover is round, but has an "Oil ledge" going from clock 12:00 to 03:00.
But searching through internet gives just few faraway mentions about such rear. The looks compared to body, and everything else senseable suggest this indeed is the original rear for this car. Even the ratio was same as from factory, and noone in their clear mind wouldnt put 2:41 again under the car, right? And housing has two big, square bulges about at 05:00 and 07:00 under the diff.cover.
Is this rare piece? Should it be under there at year 76', or is this some left-over part shelled under the car. Every mention i find tells they were assembled on roughly around ~70 +/- few years.
And to main question ( partly cause i was stupid and didnt took pics, measurements, or the bearing itself with me, and garage is far away).
Does these axles use the Timken SET9 bearing as C-clip axles? Axle seals?
Googling didnt provide any other ( okay, other brands) bearing type for outer-rear bearing atleast, but i have strong thoughts about it.
And from where do i get new bearing retaining ring? I quess it comes with the bearing.
I admit, im totally lost with this rear.
E: Heres a pic from my 76' Service Manual:
Last edited by Inline; November 18th, 2016 at 09:23 AM.
Searching whole evening, and i feel this is worthless topic. Started to found out what i wanted with tweaking search-words a bit.
I have all the right parts, if i understand it right.
SET9 bearings with retaining collars, 712146 seals. Also one confusing thing was, that the new retaining collars are, hmm lets lie from memory.. 4 times thicker than the originals.
Also got confused that i didnt have c-clips, since every place just speaks about them, but otherwise it seems to not make any difference..
Hadnt even heard about non c-clip 8.5 rears before finding out mine.
Oh well, live and learn..
Last edited by Inline; November 18th, 2016 at 11:58 AM.
Not to worry, you have the very common GM 8.5 10 bolt corporate rear end that began it's journey in 1971 and went to late 80s or early 90s I believe. Different GM divisions built them as indicated in your picture from the service manual, hence the "corporate" description. The guts were the same, but there were cosmetic differences on the covers. My 71 442 has the O built unit like in your top left photo, while my 71 SX has the Buick unit with the scalloped cover. This rear end is easy to get parts for and as you found out has the bolt in axles.
The Problem is ...Most people beat there head into a wall trying to figure out what they have with out tearing the rear down.
It is always easier to ID a rear when parts are being disassembled.
You would know the rear does not have c-clip by removing the rear cover and looking into the center cavity and removing the drum and seeing a retaining plate that hold s the axle in.
Sometimes some physical probing alleviates a lot of questions.
Also remember covers are never and usually the cause of ID problems. The housing casting NEVER changes as it will always be consistent I personally have learn the little bumps, curves, wings, recesses etc. in each GM housing. We do have some casting number written down but not all of them.... This is why I always tell people to post pictures and will ID the rear for you.
You can see all these covers could be on a 10 bolt 8.5 rear -
scalloped cover, upper 1/4 trough, smooth cover (8.2 and 8.5 standard) chevy cover 10 bolt (8.2 normally) ALL these covers fit your 8.5 10 bolt rear.
Yup- i knew i had a 8.5 since i had looked the housing, but it was just new to me there was something else than c-clip 8.5's existing. That was the thing confusing me. Another one was the original retaining ring being so much thinner than the new which comes with bearing.
Most about it, i think, is due to Chevys being so popular, that all over the internet everyone is just talking about c-clip rears, when you search about corp/GM 8.5, even NAPA etc guides you find just talk about them. That was what i was prepared for, and got confused since there were no clips to remove, and axles were too short to even hold any clip. Hadnt even noticed the little section about bolt-in axles on service manual.
But- have it figured out
E: The picture i posted was just for reference about what i talked about " 8.5 type O or B", since nobody talks about other variations, just "8.5".
Last edited by Inline; November 19th, 2016 at 11:45 AM.
all THE bop REARS FROM 1971-1976 were bolt in axles. Full size and a-body versions.... so I do not see how it can be left out unless your looking at a CHEVY fisher body assemble manual. ??
If it were a Buick, Olds or Pontiac manual it would be in there for sure.
Yes, yes it was there, just a little 1/3rd worth of page mentioning about it. And i had somehow managed to miss that information while reading it previous times, quess my eyes just read the another 1/3rd page mention about removing c-clips, since it gives instructions to both. Well, more like a one-liner " remove c-clip" or "un-bolt the 4 bolts and pull axle out".
Last edited by Inline; November 19th, 2016 at 10:54 PM.
Yes, yes it was there, just a little 1/3rd worth of page mentioning about it. And i had somehow managed to miss that information while reading it previous times, quess my eyes just read the another 1/3rd page mention about removing c-clips, since it gives instructions to both. Well, more like a one-liner " remove c-clip" or "un-bolt the 4 bolts and pull axle out".
Jim, am I correct when I say that Oldsmobile differentials were the only ones where the brake hose threads are actually in the casting and not attached to a bracket attached to a cover bolt?
Jim, am I correct when I say that Oldsmobile differentials were the only ones where the brake hose threads are actually in the casting and not attached to a bracket attached to a cover bolt?
No... ALL 10 bolt 8.5 CORP had the brake hose boss drill in the casting on top of the casting. 12 bolt Olds did also.
November 18th, 2016, 09:15 AM
