Hey all... another newbie!

I am refubishing a 1970 Cutlass S and have hit a snag on the rear end. It appears to be a standard 1970 A-Body Rear End with c-clip eliminators, 8.2 gear with 10 bolts, although the cover of the rear end has 12 bolts in it. (i'm normally a chev guy, so when I bought it I assumed a 12 bolt gear.) But once I got the diff out, it only had 10 bolts on the gear.

I ordered a replacement 8.2inch 10 bolt posi from Jeggs (an Auburn). I was about to bolt on my ring gear (in great shape) only to discover that the replacement unit not only had smaller bolt holes for the ring gear bolts, but that it is a smaller unit. (width wise)

A call to Auburn lead me to find out that with the set up I have, no one makes a simple replacement unit. They sent me to a company called Reider Racing, and I am awaiting a callback from them, but ...

Am hoping that you folks might know the "best" place to get a replacement "limited slip" differential?

Any thoughts?

TM

 

I've stumbled on these guys, and they come highly recommended, but I have not ordered from them. I will be looking at them first when it comes time to work on my differential.

http://www.jdrace.com/

HTH

 

Hey franken, JDrace is Jim from this board.
Username: Monzaz
and.... he is a great guy to deal with.

 

More than likely what you have is a true "O" rear end. Olds made their own rears for at least three years. 1968-69-70. So yea, a 12 bolt cover olds rear is only a 10 bolt. They do not have C clips like their cousins at chevy. Axles are retained at the outboard housing flange.

There a only few parts made that cater to the olds rear. There just is'nt that much available, but it can be done.

Monzaz can set you straight on this as well.

These guys still carry some parts for your rear.


http://www.supercarsunlimited.com/Ca...epartmentID=33

 

JD Race. Jim.(Monzaz) Nice guy and cares about his product. Thats who I go to. Highly Recomended. He'll build you what you want.
Tom.

 

Thanks, I put in an email inquiry into Jim's web site. Hopefully someone will call me back. A couple others I got from Auburn were Reider Racing and Accu Auto Parts. Hopefully this will works. Thank you everyone!!!! TM

 

Another source is Brian Trick on realoldspower.com forum.

 

Run, can't get that site to open.

This has been quite an experience... The vendors tell me it should be a 8.2" BOM 10 bolt..which I know doesn't work...others tell me to use a GM "O" type...but then another tells me that the traditional GM "O" type won't work. I actually measured it..the ring is 8.5" (with 6.25" center hole/hole measurement.) A guy at Accu went and got one out of the warehouse to measure and is going to call me back! Maybe a light at the end of a tunnel...but concerned if I want to put a stronger gear set that I'll have to start over again. (since it says up to 3.23).

Nothing good comes easy...Huh?!.....GRIN

 

I'll be talking to Jim later on. I'll pass the word.
Tom.

 

Try his email: Brian Trick, thetrickfamily@yahoo.com

Norm

 

There was a post on here on 3/21/2007 titled "cheap gears, who do I get some". It has some good sources for the parts you are looking for.

 

You should have the Type O rear, which had a standard strength version up to 3.23 gears, and HD with 3.42 and higher numbers. In 1966 1/2 to 68, it had 31 spline axles, 69-70 were 28 spline. Today it is something of an orphan but some stuff is available. I have the service manuals but you would run into some cost getting the pages copied.

You may want to decide how much money to put into it, vs. intended usage. It is easy to spend $2000-2500 building a really strong diff if you are going racing. The type O was good for its time, and once upon a time gears were available including 3.9, 4.33, 4.66, 5.00 but I don't think 9310 alloy pro gears were ever made for it. The O does not have c clips. Today you can build a lot more strength into other rears because of aftermarket component availability for them. If street tires are all you will use, the O is plenty strong and is consistent with the "all Olds" philosophy.

 

Get a 8.5" 10 bolt and be done with it. Stong, bolt in axles and parts are cheap and readily ava.
I just bought a used set of GM gears out of a late model GM truck and Brian Trick (listed above) cut me a great deal on a new Eaton 28 spine posi. Sell the O rear to a restorer and you will be money ahead.

 

 

Sorry put my reply in your post. New guy LOL

 

Is this what you posted?

"I have same rear you do its not a 8.2 its 8.5. Mine has a lot of play rotationaly at yolk I think from worn clutch packs no luck finding clutch kit. I believe we have o -type rears. I think BOP has brows in the case."

If so, worn clutches will not result in rotational play in the yoke; they will just let the carrier operate like an open (non posi) carrier. The O-Type uses the same clutches as the 8.5" 10 bolt rears, so they are available but are more expensive now that the supply of GM clutches in the aftermarket have all be used up.