1970-74 Chevrolet & 1973-74 GMC
Ratio code or number is stamped on forward side of axle housing tube. This identification is usually found on right tube but may be found on left tube. It is adjacent to differential housing.
Axle Ratio Codes
| Ratio | Conventional | Positive Traction | |
|---|---|---|---|
| 1970 (Chev. Only) | |||
| 3.73-1 | TDF | TDK | |
| 4.56-1 | TYS | ||
| 1971 (Chev. Only) | |||
| 3.54-1 | TKD, TKH, TKP | TKG, TKJ, TKR | |
| 3.73-1 | THL | ||
| 4.10-1 | TAJ, TJS, TKK, TKS | TJJ, JKL | |
| TJP, TJS, TKK, TKS | TJJ, JKL | ||
| 4.56-1 | TKW, TRA, TRC | ||
| TRD, TRG | |||
| 1972 (Chev. Only) | |||
| 3.54-1 | RKD, RKH | RKG, RKJ | |
| RKP, RKR | |||
| 3.73-1 | RAW | RAX | |
| 4.10-1 | RAJ, RJB, RJH, RJP | RAH, RJA, RJJ | |
| RJS, RKB, RKK, RKS | RKC, RKL, RKT | ||
| 4.56-1 | RKW, RKX, RRA | RRB, RRD | |
| RRC, RRG | RRH | ||
| 1973 (Chev. & GMC) | |||
| 3.07-1 | TAH | TAJ | |
| 3.73-1 | TBH, TLM | TBJ, TLT | |
| TLS, TLW | TLX | ||
| 4.10-1 | TFR, TKB | TFM, TKA | |
| TKD, TKM | TKC, TKL | ||
| 4.56-1 | TFZ, TKS, TKU | THB, TKR | |
| TLA, TLC | TKT, TLB | ||
| 4.88-1 | MLT | ||
| 1974 (Chev. & GMC) | |||
| 3.07-1 | TAH, KAH | KAJ, TAJ | |
| 3.73-1 | TBH, KBH, KKC | TBJ, KBJ, KKD | |
| KKF, KKM | KKH, KKN | ||
| 4.10-1 | KJS, KJU, KMF | KJT, KJW, KMH | |
| KMM, KMR, KMZ | KMN, KMU, KMB | ||
| KMA, KMC, KMJ | KMD, KMK | ||
| 4.56-1 | KFA, KFB, KFD, KRF | KFC, KFF, KRJ | |
| KRN, KRZ, KRT, KRA, KRC, KRK, KRS | KRR, KSA, KRU, KRW, KRB, KRD, KRM | ||
| 4.88-1 | KTA | ||