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Stickers1970 Chevelle Rear Axle Identification
[ 1964 ] | [ 1965 ] | [ 1966 ] | [ 1967 ] | [ 1968 ] | [ 1969 ] | [ 1970 ] | [ 1971 ] | [ 1972 ]
The rear axle identification code consists of a three letter prefix indicating the gear ratio, four digits indicating the assembly date as month/day, and a single letter suffix indicating the manufacturing location. The identification code should be stamped on the bottom or font of right axle tube either adjacent to the carrier housing or about 8" - 10" inboard from the backing plates. The particular engine RPO code is listed in parentheses as found on build sheets.
Example: CGI0629B decodes to CGI ~ 3.36:1 Positraction, 0629 ~ Month [June] and Day [29], B ~ Buffalo (G=Chevrolet Gear & Axle, W=Warren, K=McKinnon Industries). If a "1" or "2" exists, it indicates the plant shift number. See bottom of page for photo examples.
Casting Numbers:
12-Bolt Casting #3969278 - very early 1970s have
been reported with #3959038 units.
10-Bolt Casting #3969277
The casting numbers/letters on rear end housings may have either a prefix or suffix of "N" or "NF" and no reason has been found yet why they may have one or the other. Codes below are for Chevelle & Monte Carlo.
| Prefix | Axle Ratio |
| CCA | 3.08:1 ~ 10-bolt (L14/307 & L22/250)* |
| CCB | 3.36:1 ~ 10-bolt |
| CCD | 3.07:1 ~ 12-bolt Positraction |
| CCE | 3.08:1 ~ 10-bolt Positraction |
| CCF | 3.31:1 ~ 12-bolt Positraction (L34/402 & L48/350-4)* |
| CCG | 3.36:1 ~ 10-bolt Positraction |
| CCH | 2.73:1 ~ 12-bolt Positraction (L48/350-4)* |
| CCL | 2.56:1 |
| CCM | 2.56:1 ~ Positraction |
| CCN | 2.56:1 |
| CCO | 2.56:1 ~ Positraction (El Camino L34/396)* |
| CCP | 2.73:1 ~ 10-bolt (L14/307)* |
| CCW | 3.31:1 ~ 12-bolt (L34/402 & LS3/402 M.C.)* |
| CCX | 3.07:1 ~ 12-bolt |
| CGA | 2.56:1 ~ 10-bolt (L65/350-2)* |
| CGB | 2.56:1 ~ 10-bolt Heavy Duty Positraction (L65/350-2)* |
| CGC | 2.73:1 ~ Heavy Duty |
| CGD | 2.73:1 ~ Heavy Duty Positraction |
| CGE | 3.08:1 ~ 10-bolt Heavy Duty |
| CGF | 3.08:1 ~ 10-bolt Heavy Duty Positraction |
| CGG | 3.36:1 ~ 10-bolt Heavy Duty |
| CGI | 3.36:1 ~ 10-bolt Heavy Duty Positraction |
| CKC | 2.73:1 ~ Positraction |
| CKD | 2.73:1 ~ 12-bolt (L48/350-4 & LS3/402)* |
| CKF | 3.55:1 ~ 12-bolt Positraction (L78)* |
| CKJ | 3.55:1 ~ 12-bolt (L78/402)* |
| CKK | 4.10:1 ~ 12-bolt Positraction (L78/402)* |
| CRJ | 2.56:1 |
| CRK | 2.56:1 ~ 12-bolt Positraction (Monte Carlo LS5/454)* |
| CRL | 3.07:1 ~ 12-bolt |
| CRM | 3.07:1 ~ 12-bolt |
| CRU | 3.31:1 ~ 12-bolt (LS5/454 & LS6/454)* |
| CRV | 3.31:1 ~ 12-bolt Positraction (LS5/454 & LS6/454)* |
| CRW | 4.10:1 ~ 12-bolt Heavy Duty (LS6/454)* |
Positraction 4.10:1 ring gear
| 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 |
CCF ~ Positraction 3.31:1 - August 21, Buffalo
CKF ~ Positraction 3.55:1 ~ October 7, Buffalo
CCW ~ 3.31:1 - September 18, Buffalo
CCP ~ 2.73:1 - October 1, Warren, MI.
CRU ~ 3.31:1 - October 20, Buffalo, 1st shift
(Suspect stamping as the letter "C" is not consistent with
others of this year)
CCF ~ Positraction 3.31:1 - November 6, Buffalo, 1st shift
CCF ~ Positraction 3.31:1 - November 10, McKinnon ~ Courtesy Dane
Belden
CCF ~ Positraction 3.31:1 - November 20, Buffalo, 1st shift
CRV ~ Positraction 3.31:1 - November 26, Buffalo, 1st shift
CRV ~ Positraction 3.31:1 - December 05, Buffalo, 2nd shift
CRV ~ Positraction 3.31:1 - December 08, Buffalo, 2nd shift
CRV ~ Positraction 3.31:1 - December 22, Buffalo, 1st shift
CCW ~ 3.31:1 - January 9, Buffalo, 2nd shift
CRW ~ Positraction 4.10:1 - February 12, Buffalo, 1st shift
(Suspect stamping as the letter "C" is not consistent with
others of this year)
CCW ~ 3.31:1 - February 16, Buffalo, 2nd shift
CCH ~ Positraction 2.73:1 - February 18, Buffalo, 1st shift
CCW ~ 3.31:1 - February 27, Buffalo, 1st shift
CKD ~ 2.73:1 - March 20, Buffalo, 1st shift
CCF ~ Positraction 3.31:1 - March 25, Buffalo, 1st shift
CCF ~ Positraction 3.31:1 - April 8, Buffalo, 2nd shift
CRV ~ Positraction 3.31:1 - April 10, Buffalo, 2nd shift
CKD ~ 2.73:1 - April 15, Buffalo, 2nd shift
CCF ~ Positraction 3.31:1 - May 21, Buffalo, 1st shift
CRW ~ Positraction 4.10:1 ~ May 27, Buffalo, 2nd shift
CGA ~ 2.56:1 - June 02, Buffalo, 1st shift
CRW ~ Positraction 4.10:1 - June 03, Buffalo, 2nd shift
CF ~ Positraction 3.31:1 - June 27, Buffalo (Appears someone was lazy
and only stamped this CF instead of CCF)
Casting Date Examples
Casting date example of I 8 9 for September 8, 1969
Casting date example of J 10 9 for October 10, 1969
Casting date example of K 10 9 for November 10, 1969
B 27 0 for February 27, 1970
C 5 0 for March 5, 1970
Casting date example of E 8 0 for May 8, 1970
Casting date example of E 11 0 for May 11, 1970
Casting date example of F 24 0 for June 24, 1970
Casting date example of G 28 0 for July 28, 1970
Casting Number Examples
1970-1972 ~ Variations of casting number 3969278
* Engine RPO code and size following the rear axle ratio are taken from build sheets and/or Protect-O-Plates and may not reflect the only engines the rear axle codes came with. Where there are no RPO/engine information following the rear axle code only means I do not have build sheets and/or Protect-O-Plates to verify them.
