guys, where can I get some info on the w27 rear end with the aluminum 3rd member housing. Specifically, is there a manual or just a regular olds (GM) 12 bolt equipment for internals. I'm having a hard time finding anything out about this thing. Thanks for helping.

 

It was a 1970 only option and was an Oldsmobile "O" axle with the special aluminum center section. It is NOT a 12 bolt like the Chevy axle. It does have a 12 bolt cover, but uses a 10 bolt ring gear and bolt in axles. It has nothing in common with the chevy 12 bolt axle aside from the bolt pattern and brake hardware. They stopped using the aluminum center section housings due to a high rate of axle failure under high loads in drag racing and made the option the aluminum cover only. Any axle that blew up was replaced with an iron housing and retained the aluminum cover.

 

So it uses 10 bolt internals, but the axle is not a c-clip, but has a bolt in (aka c-clip eliminator) type axles. The one that I have is empty and I'd like to build it up. Any suggestions on those bolt in axles? Did any other GM 10-bolt use that or ? Thanks for your reply btw.

 

Do you have the W27 housing? If so it's a 1970 housing and requires 1970 axles and they changed the bearings and seals in 1970 and the 67-69 units won't interchange.
The carriers can be found but are not cheap and will be used.
The clutch packs are the same as the ones used on the 8.5 posi that was used in the Grand Nationals, but they have been discontinued as of last year.
Don't think of the axles as "C-clip eliminators" because they are not. They are simply bolt in axles. The same type of mounting as a Ford 9".
I have heard of someone converting a Ford 8.8 diff to use the Type-O ring gear so that is always a possibility as well.

 

Yes, I have an empty W27 3rd member, tubes and cover. It has no axles or carrier. It sounds like this will be an interesting scavenger hunt or I need to find some one with the internals that wants the housing. I have no need for it, but realize it might be easier to sell if it is complete. I'd like to get it to an Olds collector that will put it under a car for a fair price. What's a fair price?

 

That's a tough one.
Try contacting Brian Trick. He is a rear end guru and would be a bit more help with this.
Here is his email.

thetrickfamily@yahoo.com