GM PRODUCTION OPTIONS RPO FY LY DIVISIONAL RPO DESCRIPTION SPOGM RPO DESCRIPTION G66 76 88 ABSORBER AIR BOOSTER RR SHOCK W MAN LVL CONT G66 G67 76 77 ABSORBER AUTO LEVEL CONTROL SHOCK SYSTEM W A L C G67 G67 78 89 ABSORBER ELEC LEVEL CONTROL SHOCK SYSTEM W ELEC LVL CONT G67 G72 80 80 AXLE RR 2 14 RATIO W 2 14R G72 G72 81 81 AXLE RR 2 14 RATIO EXPORT W 2 14R G72 EXPORT G72 82 87 AXLE RR 2 14 RATIO W 2 14R G72 G75 82 87 AXLE RR 3 62 RATIO W 3 62R G75 G80 76 89 AXLE RR LOCKING TYPE LIMITED SLIP W G80 G83 82 83 GEAR RING 8 75 W 8 75 DIA RNGR G83 G87 76 88 GEAR RING 8 50 W 8 50 DIA RNGR G87 G88 76 83 GEAR RING 8 875 W 8 875 DIA RNGR G88 A G89 76 87 GEAR RING 7 50 W 7 50 DIA RNGR G89 G92 76 88 AXLE PERFORMANCE RATIO W G92 G95 85 88 AXLE ECONOMY RATIO W G95 HA3 82 89 AXLE RR 5 29 RATIO W 5 29R HA3 HC2 76 81 AXLE RR 2 76 RATIO W 2 76R HC2 HC4 76 89 AXLE RR 4 56 RATIO W 4 56R HC4 HC7 76 89 AXLE RR 5 13 RATIO W 5 13R HC7 HC8 76 87 AXLE RR 3 21 RATIO W 3 21R HC8 HD1 82 84 AXLE RR 5 83 RATIO W 5 83R HD1 HE3 76 84 AXLE RR 3 07 RATIO W 3 07R HE3 HE4 76 81 AXLE RR 3 40 RATIO W 3 4OR HE4 HF7 76 89 AXLE HEAVY DUTY RR 4 56 RATIO W H D 4 56R HF7 HF8 76 89 AXLE RR 4 88 RATIO A W 4 88R HF8 HK1 B2 86 AXLE RR 2 87 RATIO W 2 87R HK1 HK9 82 84 AXLE RR 5 86 RATIO W 5 86R HK9 H04 76 88 AXLE RR 4 11 RATIO W 4 11R HO4 H22 76 81 AXLE RR 6 17 RATIO W 6 17R H22 H23 76 81 AXLE RR 5 43 RATIO W 5 43R H23 I H4D 85 85 EMISSIONS CONTROLZ6 CYL SPRING OPERATED EFE W EMIS CONT H4D H4D 85 85 28 CYL CAST IRON EXH MANIF W EMIS CONT H4D H5D 85 85 EMISSIONS CONTROL 6 CYL VACUUM OPERATED EFE W EMIS CONT H5D HSD 85 85 8 CYL STAINLESS STEEL EXH W EMIS CONT H5D JA1 76 88 BRAKE SYSTEM POWER LIGHT DUTY W JA1 JA2 76 88 BRAKE SYSTEM POWER HEAVY DUTY W JA2 JA3 76 83 BRAKE SYSTEM POWER STATION WAGONS W JA3 JA3 84 86 BRAKE SYSTEM POWER EXTRA HEAVY DUTY W JA3 JA4 76 81 BRAKE SYSTEM DISC DRUM W JA4 JA5 76 85 BRAKE SYSTEM POWER HEAVY DUTY W JA5 JA6 76 81 BRAKE SYSTEM MANUAL EXTRA LIGHT WEIGHT W JA6 JA7 86 89 HANDLE LEATHER PARK BRAKE RELEASE W LEA BRK HDL JA7 JA8 82 88 BRAKE SYSTEM POWER MEDIUM DUTY W JA8 JB1 76 89 BRAKE SYSTEM MANUAL DISC DRUM W JB1 JB2 76 81 BRAKE SYSTEM DISC DRUM W JB2 A JB3 76 89 BRAKE SYSTEM VACUUM POWER DISC DRUM W JB3 JB5 76 89 BRAKE SYSTEM VACUUM POWER DISC DRUM W JB5 JB6 76 89 BRAKE SYSTEM VACUUM POWER DISC DRUM W JB6 JB7 76 89 BRAKE SYSTEM VACUUM POWER DISC DRUM W JB7 JB8 76 89 BRAKE SYSTEM HYDRAULIC POWER DISC DRUM W JB8 JC4 82 87 BRAKE FRT VENTED ROTOR W JC4 JD3 76 87 BRAKE SYSTEM VACUUM POWER DISC DRUM W JD3 JD5 76 89 BRAKE SYSTEM POWER DISC W JD5 JD6 76 89 BRAKE SYSTEM HYDRAULIC POWER DISC DRUM W JD6 JD7 76 89 BRAKE SYSTEM HYDRAULIC POWER DISC DRUM W JD7 JE1 76 89 BRAKE SYSTEM EUROPE EXPORT W JE1 EXPORT JF9 76 89 BRAKE SYSTEM HYDRAULIC POWER 4 WHEEL DISC W JF9 JG1 88 88 SHAFT PROP ALUMINUM W JG1 JL1 76 83 PADS CUSTOM PEDAL TRIM W CUST PADS JL1 JL2 76 83 BRAKE SYSTEM FRT POWER DISC W JL2 JL5 82 83 BRAKE FRT SOLID DISC W JL5 JL6 76 89 BRAKE SYSTEM MANUAL DISC DRUM CAST IRON W JL6 JL9 87 89 BRAKE SYSTEM POWER FRT RR DISC ANTILOCK W JL9 JM3 88 89 BRAKE BOOSTER DOUBLE DIAPHRAM HI FLOW 24OMM W BOOS JM3 JM4 86 89 BRAKE SYSTEM POWER ANTILOCK CAST IRON W JM4 JM5 82 89 BRAKE BOOSTER DOUBLE DIAPHRAGM 200MM W BOOS JM5 JM7 76 89 BRAKE BOOSTER SINGLE DIAPHRAGM W BOOS JM7 JM8 76 87 BRAKE SYSTEM POWER ANTILOCK ALUMINUM W JM8 J41 82 89 BRAKE SY5TEM POWER DISC DRUM CAST IRON W J41 J42 82 88 BRAKE SYSTEM POWER DISC DRUM ALUMINUM W J42 J5O 76 89 BRAKE SYSTEM VACUUM POWER W J5O J55 76 89 BRAKE SYSTEM HEAVY DUTY POWER VAR 1 W J55 L 1988 GENERAL MOTORS SERVICE PARTS OPERATIONS LT TRUCK 52R RPO 12 REV 1 88