Hi all, i just got my 70 frame/chassis back blasted and painted and i would like to find out how to decode it. It has 3960733 s 276 (the s is inside a circle) and underneath those numbers is this 1 21 n1 xu.. This frame is supposed to come of an originall ss 396 and it also has a 12 bolt rear axel with the code of CKD 032681 .. Any help will be appreciated, tnx... graemlins/beers.gif

According to my GM parts book:


The top line of the identification will provide the part number of the frame assembly, the name of the manufacturer (abbreviated, ie, Pontiac-Pon, A.O. Smith-S, Parish Pressed Steel-P.P.S.)

The bottom line will provide the month, day, year and shift number.I didn't find '3960733' as a part number. My GM parts book (circa 1971) shows 3992389 as a 69-71 Chevelle 2-dr and 6235665 as 68-72 wagon and El Camino. But...part numbers are superceded all the time.

The rest looks like A.O. Smith (the s in the circle) and 276 could be a tracking number for them (?). The second line looks like Jan 21 (1 21), night shift (n and/or 1), XU is code for 2-dr sport coupe frame.

CKD is correct for a 70 2.73 open rear end. 0326 part would be Mar, 26 and I'd venture to guess the '81' is really 'B1' for Buffalo (B) day shift (1).