Was wondering if anyone had the means to decode the diff ID code on the axle tube. I got part of it figured out.

UA P 029N

I found the following in my service manual:
Open diff.
2.73 gear ratio from the UA
8-7/8" ring gear from the P

What is the date code, as well as the N at the end of it?

Thanks.

 

Just thinkin...

029N = 29th day of November?

 

Your thinking is probably mostly correct. The O is really and "OH" for Olds axle. Other than that I think you nailed it. I just found this thread on a related search.

 

When was your car built?The 029 should mean the 29th day of the year,which would be Januray 29th.The "N" could be the plant code.

 

Wow, forgot about this thread. I just found it again searching for gears on Google...

I'd have to check and see exactly when the car was built.

While I've got you all reading this old thread again though.... anyone know what gears are available for this 10-bolt 8.875 rear end? I'm not really finding any info out there. I heard there isn't much aftermarket for the 10 bolt GM 8.875 car diff.

 

No,there isn't much available for those.Every once in awhile,you might see a set of 3:23 gears for these rears pop up for sale.

 

You mean a set of 3.23s from out of another Olds, or new?

Are these diffs the 10 bolt cover 12 bolt ring gear I've heard of? If so, the gears for regular GM passenger car 12 bolt 8.875 I see for sale all over would not work, would they? Browsing the net it's like these didn't ever exist!

Thanks.

 

A used set,from another car.

 

Well I found these...

http://stores.ebay.com/Fabcraft-Meta...=p4634.c0.m322

Anyone have any experience with them? Seem to be only available in 3.55 though... and somewhat pricey.