CRG Discussion Forum

Camaro Research Group Discussion => Decoding/Numbers => Topic started by: Badshifter on May 24, 2022, 10:49:05 PM

Title: 1969/1970 12 bolt rear service replacement part? 3969341NF
Post by: Badshifter on May 24, 2022, 10:49:05 PM

I was just given a 12 bolt pulled from an ex race car and want to see if I've decoded the numbers correctly. It's just the housing, no gears, axle or diff.
Casting Number 3969341NF - late 69 early 70?
Casting Date C190 - March 19th 1970?
Axle Tube stamp C OS (or) C QS 0421G2 - OS (QS) 2:56 4WD (4 wheel disc?) April 21st Detroit Gear 2nd shift?

Is the 4WD indicative of a Service Replacement Part?

Thank you for any help.

Title: Re: 1969/1970 12 bolt rear service replacement part? 3969341NF
Post by: KurtS on May 31, 2022, 03:59:04 PM

1970 3.07 axle.

Title: Re: 1969/1970 12 bolt rear service replacement part? 3969341NF
Post by: Badshifter on June 01, 2022, 01:34:19 AM

Thank you Kurt.

Title: Re: 1969/1970 12 bolt rear service replacement part? 3969341NF
Post by: Rossterman on November 08, 2022, 08:28:59 PM

Correct for a 70 SS camaro

Title: Re: 1969/1970 12 bolt rear service replacement part? 3969341NF
Post by: ko-lek-tor on November 10, 2022, 02:07:12 AM

Most likely Nova. Measure length. Here is a chart:

Title: Re: 1969/1970 12 bolt rear service replacement part? 3969341NF
Post by: bertfam on November 10, 2022, 02:33:05 AM

Quote

Most likely Nova.

COS is a 1970 3.07 Camaro axle.

Ed

Title: Re: 1969/1970 12 bolt rear service replacement part? 3969341NF
Post by: rare396bronze on November 10, 2022, 02:53:44 AM

You beat me to it Ed. There is no CQS listed in Chevrolet by the numbers. But COS is listed as Camaro 3.07. Nice find. 70 12 bollts are hard to find since they did away with the 12 bolts on Camaro after 1970.