Buick posi I.D.

Questions about all other brand differentials.
GMRESTO
Newbie Poster
Posts: 6
Joined: Fri Apr 24, 2009 4:58 pm

Buick posi I.D.

Postby GMRESTO » Sat Apr 25, 2009 8:44 am

Have a rear axle that is supposed to be out of a Riviera. Told it's a 9.375 posi. The numbers stamped into the front of the passenger side tube are " QJ 0285 ". Can it be identified from this ? Thanks in advance. GMRESTO

User avatar
monzaz
Average Poster
Posts: 840
Joined: Tue Nov 13, 2007 7:56 pm
Location: RICHFIELD, OH

Re: Buick posi I.D.

Postby monzaz » Sat Apr 25, 2009 7:38 pm

Need the exact year but from that code it appears to be a 3.07 open diff. Jim
J D Race

GMRESTO
Newbie Poster
Posts: 6
Joined: Fri Apr 24, 2009 4:58 pm

Re: Buick posi I.D.

Postby GMRESTO » Mon Apr 27, 2009 2:47 pm

You are right about the ratio, but it is a posi. Thanks for the help. GMRESTO

User avatar
monzaz
Average Poster
Posts: 840
Joined: Tue Nov 13, 2007 7:56 pm
Location: RICHFIELD, OH

Re: Buick posi I.D.

Postby monzaz » Tue Apr 28, 2009 6:58 am

Unfortunately no it says it is a open. BUT it is always best to check. raise the one tire off the ground and spin the wheel off the ground... IF you can , then it is NOT posi IF you CAN NOT sping the axle then it is posi...or if it is very hard to spin the wheel with alot of force it could be a posi on its last legs. Jim
J D Race

GMRESTO
Newbie Poster
Posts: 6
Joined: Fri Apr 24, 2009 4:58 pm

Re: Buick posi I.D.

Postby GMRESTO » Tue Apr 28, 2009 3:17 pm

Pulled the cover off(12 bolts) and see the preload spring and clutch packs. Ring gear is also 12 bolt. Still don't know what kind of animal it is or what vintage. Thanks for the help. Carl

User avatar
monzaz
Average Poster
Posts: 840
Joined: Tue Nov 13, 2007 7:56 pm
Location: RICHFIELD, OH

Re: Buick posi I.D.

Postby monzaz » Sun May 03, 2009 9:33 am

PICTURES...lets see what you have. The ratio will be on the outer diameter edge of the ring gear. wipe and look for it as you spin the carrier/posi unit around.
J D Race

GMRESTO
Newbie Poster
Posts: 6
Joined: Fri Apr 24, 2009 4:58 pm

Re: Buick posi I.D.

Postby GMRESTO » Thu May 07, 2009 9:46 pm

It has an 'S' spring between the side gears instead of coil springs. The ring gear, still installed, measures over 9 1/4", so must be 9.375. Ring gear has 41 teeth. Markings on ring gear as follows; 41B14 GM 275 1. Clutch plates have square ears. Was told recently that it came out of a '71 to '73 Riviera. Can it be identified with this info plus the 'QJ 0285' stamped on the front of the right hand tube ? If you can ID it, are parts readily available ? Thanks for your time and expertise. Carl

User avatar
monzaz
Average Poster
Posts: 840
Joined: Tue Nov 13, 2007 7:56 pm
Location: RICHFIELD, OH

Re: Buick posi I.D.

Postby monzaz » Mon May 11, 2009 11:46 am

Carl, Big ZERO of the parts. you have a 14 and 41 ring and pinion combo which translates to 2.93 ratio...NOT quite 3.08 which will be 13 and 40. You have to remember these were NOT race cars in the day. That was a pretty good ratio for what the car was. Anything in the 3's was pretty much performance back then especially in the 70's. Sounds like you might have a 'O' type full size 12 bolt rear. Is the cover round and have a symmetrical gasket. Look at the pictures and see if it looks like that one. Jim
Attachments
rears 018.jpg
olds 88 014.jpg
J D Race

GMRESTO
Newbie Poster
Posts: 6
Joined: Fri Apr 24, 2009 4:58 pm

Re: Buick posi I.D.

Postby GMRESTO » Tue May 12, 2009 11:40 am

You figured out what I have ! Thanks a lot for the time you spent. Do you have bearings, planetary gears, clutch plates, seals, shims, crush sleeves, or any other overhaul parts ? could you tell me what car or cars this would have come out of ? Thanks again for the help. Carl P.S. Found the raised numbers cast into the carrier. They are 761.

User avatar
monzaz
Average Poster
Posts: 840
Joined: Tue Nov 13, 2007 7:56 pm
Location: RICHFIELD, OH

Re: Buick posi I.D.

Postby monzaz » Thu May 14, 2009 10:00 pm

Hey the site works...lol. Glad we can help. NOW for the bad news. Parts are VERY limited. The clutches can be purchased and are the same as 8.5 chevy posi units. We have them in stock but the price is outrageous 195.00 for clutches. Are you sure they are bad? Most I have run across just need a little re shimming and your good to go again .
761 casting holds 2.73 -2.93 I think. I am still learning all the ratios for this rear. CALLED the FULL SIZE 'O' type 12 bolt Oldsmobile rear. So most full size oldsmobiles will have these rear and all the way into the 1974 cars too. Guts will al be the same even though the yoke or mounting points on the rear are different.

I could use some more info too. what gears are in your car? that you have a 761 casting posi. Just gathering info where I can to keep on helping. Jim

I can get you all the bearings no problem. The crush sleeve could be an issue. rear cover gasket will probably be a bit harder too. front pinion seal should nopt be a problem. All in all we should be able to get you the parts you need...Just maybe a little more expensive than a 12 bolt chevy or 10 bolt 8.5 ...lol. Jim :)

Check out the left column next time for the differetial ID button and look for some of the button that have different size rears.
J D Race

GMRESTO
Newbie Poster
Posts: 6
Joined: Fri Apr 24, 2009 4:58 pm

Re: Buick posi I.D.

Postby GMRESTO » Mon Jul 20, 2009 3:00 pm

Jim, Thanks for the reply. No 12 bolt 9 3/8" in the ID box to left. FYI pinion bearing inside diameters are 1.313" and 1.865". There are 30 splines on the pinion and a dab of 'PINK' paint on the front of splines. Ring gear is 9 3/8" with 12 Left Hand thread bolts. Inside diameter is 6.020". P/N is 41B44 CI (?) HN .275 1 . The Axles are 31 spline. The carrier casting is '671'. Will a 3.08 R and P (maybe with a spacer) fit this ? Thanks in advance.

User avatar
monzaz
Average Poster
Posts: 840
Joined: Tue Nov 13, 2007 7:56 pm
Location: RICHFIELD, OH

Re: Buick posi I.D.

Postby monzaz » Tue Jul 21, 2009 9:22 am

Yes a spacer may work with the rear...BUT we need to make a spacer as I do not know if one exsists. I think if you can get your hands on a pontiac old 57-64 drop out ring gear spacer the metal ring may fit and may only need a redrill over sized of the bolt holes IF they are not big enough. Longer left hand thread bolts are available too seperately. Again everything is not goingh to be super cheap BUT is do able. Jim

I have a LOW carrier here we can mock the spacer with. Jim
J D Race


Return to “General Differential Questions”

Who is online

Users browsing this forum: No registered users and 3 guests