1972 Chevelle Rear Axle Identification
The rear axle identification code consists of at least a two letter prefix indicating the gear ratio, a letter for the rear axle plant, and three digits indicating the day of the year from January 1. The identification code should be stamped on the bottom or front left or right axle tube either adjacent to the carrier housing or about 8" - 10" inboard from the backing plates.
Example: CHC0642E decodes to CHC ~ 2.73 Positraction, 064 ~
day of year starting with January 1 (the 64th day being
March 5), Chevrolet, 1 or 2 ~ shift (if
present), - ~ no Positraction, p ~ Positraction, E ~ Eaton Positraction
B = Buick, O = Olds,
C or G = Chevrolet, K or M = McKinnon Industries, or P
= Pontiac.
Casting Numbers:
12-Bolt Casting #3969278
10-Bolt Casting #3969277
| Prefix | Axle Ratio |
| GD | 2.73 ~ Positraction |
| GF | 3.08 |
| CH | 2.73 ~ Positraction |
| GA | 2.56 |
| GC | 2.73 |
| GG | 3.36 |
| GB | 2.56 ~ Positraction |
| GI | 3.36 ~ Positraction |
| KD | 2.73 |
| CW | 3.31 |
| CF | 3.31 ~ Positraction |
| RU | 3.31 |
| RV | 3.31 ~ Positraction |
| RW | 4.10 |
| GH | 2.73 |
| GN | 3.08 |
| Assembly Month - 1st and 2nd numbers | |||
| Number | Month | Number | Month |
| 01 | January | 02 | February |
| 03 | March | 04 | April |
| 05 | May | 06 | June |
| 07 | July | 08 | August |
| 09 | September | 10 | October |
| 11 | November | 12 | December |
Assembly Day - 3rd and 4th numbers
01...31
|
Rear Axle Assembly Plant - 5th letter |
|
| Code | Assembly Plant |
| B | Buffalo ~ New York |
| G | Chevrolet Gear & Axle |
| W | Warren ~ Michigan |
| K | McKinnon Industries |
