CRG Discussion Forum

Camaro Research Group Discussion => Decoding/Numbers => Topic started by: red69 on December 27, 2023, 03:29:46 PM

Title: Rear axle code question
Post by: red69 on December 27, 2023, 03:29:46 PM
I'm a little confused by the coding on this rearend. Maybe I'm reading the charts wrong. The casting reads C289 (March 28 69). The housing stamp reads C  BL 0120G2 (3.07 open January 20 Detroit 2nd shift) right? And why the C in front?
Title: Re: Rear axle code question
Post by: bcmiller on December 27, 2023, 04:25:48 PM
Does the center housing casting number end in 860 or 341?

Post all of the area by the stamping, with at least 1 inch extra on each side.

It seems that you might have a 1970 Nova rear end.

The 3 letter format for axle codes started around August of 1969. See this related thread.

http://www.camaros.org/forum/index.php?topic=10375.0
Title: Re: Rear axle code question
Post by: Z10Mike on December 27, 2023, 11:26:32 PM
 Casting date late March 69 and final assembly Jan 20, 1970.  That is a long time, but would indicate that Gear & Axle used whatever components were on hand to complete an axle assembly.  Probably not "normative" but the plants didn't operate on that principle.
Title: Re: Rear axle code question
Post by: red69 on December 28, 2023, 03:19:33 PM
Casting # and larger stamping pics.
Title: Re: Rear axle code question
Post by: bcmiller on December 28, 2023, 04:05:57 PM
It is not common, but it looks like this was a leftover 860 casting that got used for a Nova rear end in January 1970.

The changeover from the 860 to the 341 casting took place in the Summer of 1969.  This is the first time I can remember an older casting being used for a rear end, but it has happened before on a few engines.
Title: Re: Rear axle code question
Post by: red69 on December 29, 2023, 01:34:15 AM
Thanks for the info. That’s a longtime for that casting to sit around before assembly. Nova rearend must be all the same dimensions as it bolted right in the 67 Camaro.
Title: Re: Rear axle code question
Post by: bcmiller on December 29, 2023, 04:01:05 AM
The 68 to 72 Nova 12 bolts ARE the same dimensions.

I found a CBS coded 70 Nova 12 bolt for my nephews 69 Camaro and another CBS for my dad’s 70 Nova.