TRUCK REAR AXLE PRODUCTION CODE NUMBER LOCATIONS Chevrolet Single Speed Truck Stamped on forward upper surface of differential carrier housing Chevrolet 2 Speed Truck Same as single speed Dana Single Speed Truck Stamped on the right tube rear side adjacent to the differential carrier housing Axle ratio on metal tag attached to differential carrier A Eaton Single Speed Truck Stamped on top surface of differential carrier housing Eaton 2 Speed Truck Stamped same as Eaton Single Speed Truck Eaton Tandem Truck Forward unit stamped on left side of differential carrier housing rear unit stamped on top surface of differential carrier housing I C O P O or special equipment axles will be coded as follows SOURCE CODE n Eaton Single Speed Air Brake AE1A Eaton Single Speed Hydraulic E1H l Eaton A Two Speed Air Brake E1A Eaton t Two Speed Hydraulic E2H I Rockwell Single Speed Air Brake R1A E Dana Single Speed D1A 1971 REAR AXLE IDENTIFICATION I AXLE MODEL AXLE MODEL r CODE APPLICATION RATlO I i CODE APPLICATION RA1 Q TAA C 10 P 10 3 73 1 THZ C 10 4 11 1 P Trac i TAB C 10 P 10 4 57 1 Power Lok TJA C 20 4 10 1 No Spin TAC C 30 P 30 4 57 1 TJB C 20 4 10 1 TAD C 30 P 30 4 57 1 Power Lok TJC C 20 4 57 1 A TAG C 30 P 30 4 57 1 TJD l 20 4 57 1 TAH C 20 P 20 4 10 1 Power Lok TJG l 20 4 57 1 No SPI A TAJ C 20 P 20 4 10 1 i TJH K 20 4 10 1 TAK C 30 P 30 r 4 10 1 TJJ K 20 4 10 1 No Spin TAL C 30 P 30 4 10 1 Power Lok TJK C 30 4 10 1 No Spin TAP C 30 P 30 4 10 1 TJL C 30 5 14 1 No Spin TAS C 30 P 30 6 17 1 TJP A C 20 4 10 1 TAT A 3990076 6 17 1 Power Lok TJR C 20 4 57 1 TDA G 30 4 57 1 TJS A C 20 4 10 1 TD8 G 30 4 10 1 I TJT C 20 4 57 1 i TDC G430 4 57 1 TJW l 20 4 57 1 TDD G 10 3 07 1 TJX C 10 3 54 1 TDG G 10 3 07 1 P Trac TJY C 10 3 54 1 Power Lok TGA C 20 P 20 4 57 1 TJZ C 10 3 54 1 TGB P 20 4 10 1 Tl A C 10 3 54 1 Power Lok TGG P 30 4 10 1 TKB 3987491 4 10 1 TGH P 30 4 57 1 A TKC 3987492 4 10 1 Power Lok TGJ P 30 4 57 1 Tl D C 20 3 54 1 A TGK P 30 4 57 1 A TKG C 20 3 54 1 Pow r Lok A TGL P 30 4 57 1 TKH C 20 3 54 1 TGP P 30 A 5 14 1 A TKJ C 20 3 54 1 Power Lok THA C 10 3 07 1 TKK C 20 4 10 1 A THB C 10 3 07 1 P Trac TKL C 20 4 10 1 Power Lok THC C 10 P 10 3 73 1 i TKP C 20 I 3 54 1 THD C 10 P 10 4 11 1 A TKR C 20 3 54 1 Power Lok THG C 10 4 11 1 P Trac Tl S C 20 4 10 1 THH K 10 3 07 1 TKT 3988404 4 10 1 Power Lok THJ K 10 3 07 1 P Trac TI W K 20 4 56 1 i THK K 10 3 37 1 TKX 3988407 4 56 1 Power Lok TH L l 10 3 73 1 P Trac TI V 3988408 4 11 1 THP C 10 4 57 1 No Spin TKZ 3988409 4 11 1 Power Lok THR C 30 4 57 1 No Spin TPR G 10 3 35 1 V THS C 10 3 07 1 TPS G 10 3 36 1 P Trac A THT C 10 3 07 1 P Trac TPG G 20 3 07 1 THW C 10 3 73 1 TPH G 20 3 07 1 P Trac THX P C 10 3 73 1 P Trac TPJ G 20 3 73 1 THY C 10 I 4 11 1 TPK G 20 3 73 1 P Trac T GM PARTS DIVISION GENERAL MOTORS CORPORATlON CHEVHOLET 72TL I 67