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Drive Axle Ratio Identification: Identification

Identification code for rear axles is stamped on rear surface of right rear axle tube. Identification code for front axles is stamped on top rear of left axle tube. On Dana built front axles, axle ratio code is on tape stripe around right front axle tube.

"C, G, K & P" AXLE RATIO IDENTIFICATION (FRONT)

Code Ratio
HAN 2.73:1
HAP 3.08:1
HAU, MKB 3.23:1
HAR, HAW, MHC 3.42:1
HAS, HAT, MBC, TBA, TBB 3.73:1
GBB, MCD, TCA, TCB 4.10:1
TDA, TDB 4.56:1
"C, G, K & P" AXLE RATIO IDENTIFICATION (REAR, NON-LOCKING)

Code Ratio
BB3, BRA, BRD, BR3, BX3, CK3, CN3 2.73:1
BC3, BSA, BSC, BSD, BS3, BY3, CRE 3.08:1
GGF, GGK, GMA, GMG 3.21:1
BDC, BDB, BDD, BDF, HBG 2.23:1
BBC, BBD, BBJ, BBK, BBN, BBR, BD3, BT3, BZ3, CA3, CX3, HMR 3.42:1
BCY, BCW, BCX, BFA, BFK, BFN, BFU, BFW, BF3, BUE, CY3, GDF, GGG, GGL, GGP, GGY, GHB, GLH, GMB, GMH, GMP, GMW, HBB, GHN 3.73:1
BCZ, BHK, GDL, GGH, GGM, GGZ GHC, GHM, GHR, GLJ, GLP, GLS, GLU, GMD, GMK, GMS, HBD 4.10:1
BKC, BKN, GDC, GGJ, GGN, GHA, GHD, GHN, GHS, GLL, GLR, GLT, GLW, GMM, GMT, HBJ 4.56:1
BKT 4.88:1
BNB, GHU 5.13:1
TSA 5.29:1
TTA 5.83:1
"C, G, K & P" AXLE RATIO IDENTIFICATION (REAR, LOCKING)

Code Ratio
BH3, BRF, BRH, CC3, CJ3, CS3, CU3 2.73:1
AZ3, BJ3, BRB, BSB, BSF, BSH, CD3, CT3, CW3 3.08:1
HBH 3.23:1
BA3, BBA, BBF, BBH, BBM, BBS, BBT, BK3, CF3, CZ3, HMS 3.42:1
BDA, BFC, BFD, BFF, BFH, BFJ, BFM, BFR, BFX, BFY, BM3, DA3, GDG, GGU, GHF, GHJ, GLK, GMC, GMJ, GMR, GMX, HBC, HPB 3.73:1
BJA, BJB, BJD, GDK, GGR, GGW, GHG, GHK, GLM, GLX, GMF, GML, HBF 4.10:1
BKD, GDD, GGT, GGX, GHH, GHL, GHP, GHT, GLN, GLY, GMN, GMU, HBK 4.56:1
ASTRO, SAFARI & "S" SERIES AXLE RATIO IDENTIFICATION

Code Ratio
Conventional Rear Differentials
FAA 2.56:1
FCA, FCB 2.73:1
FFA, FFB, GNH, GNM, GNX 3.08:1
FMA, FMB, GNJ, GNN, GNT, GNY, GPB 3.42:1
FRA, FRB, GNK, GNP, GNU, GNZ, GPC, GPG 3.73:1
FSA, FSD, GNL, GNR, GNW, GPA, GPD, GPH 4.11:1
Locking Rear Differentials
FBA 2.56:1
GNS 3.08:1
GPF 3.42:1
Front Differentials
GBD 3.42:1
GBF 3.73:1
GBG 4.11:1