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General Motors

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.

REAR AXLE RATIO IDENTIFICATION (GENERAL MOTORS) CONVENTIONAL DIFFERENTIALS

Code Ratio
TFR, TFM, TFD, TFT, TFC, TNA, RNA, TFW, TEX 2.56:1
TAJ, TDA, TAY, TAA, TDF, RUR, TAF, TDJ 2.73:1
TBA, TBK, KXC, KXA, KXJ, KXM, RYJ, TBW, TBF 3.08:1
RMR, KKA, RMM 3.21:1
TKK, TKM, TKN, TKR 3.23:1
TCH, RCA, RCX, RKB, KHN, KHU, KDB, RCH, RZK, KHJ, KMK, TCD, RCS 3.42:1
RBZ, RJB, RBC, KBM, RKJ, TJK, KBK, TJN, TJS 3.73:1
RRM 3.75:1
KND 4.09:1
RHN, KUD, RHD, KUN, RHC, KUB, KMH 4.10:1
TRB, KSF, KSZ, KRJ, KFT, TRB, KRU 4.56:1
LOCKING DIFFERENTIALS

Code Ratio
TFU, RNA, RNB, TNB, RNC, TFY, TFZ 2.56:1
TDB, TDD, RUK, RUM, TDH, RUN, TDM, TDN 2.73:1
KXD, KXH, KXK, RYA, RYF, KXR, RYH, TBY, TBB 3.08:1
KKD, RMN 3.21:1
RCB, RCZ, KZH, RZH, KHT, KDA, RCR, RZJ, KHM, KHW, KHS, RCU 3.42:1
RBD, KBW, RJF, TJM, KKU, TJR, TJT 3.73:1
RRN 3.75:1
KNF 4.09:1
RHR, KUF, RHM, KUR 4.10:1
TRC, KSH, KWB, KRK, KFZ, TRC, KRW, KSU 4.56:1
FRONT AXLE RATIO IDENTIFICATION

Code Ratio
WK 2.56:1
WA 2.73:1
WB 3.08:1
WC, WD 3.23:1
WF, WH, WJ 3.42:1
WM, WW 3.73:1
WY 4.10:1