AXLE IDENTIFICATION CODES CONT D INDICATES POSITRACTION 1990 B 2 56 RATIO GM8 OPTION 2 73 RATIO GU2 OPTION 2 93 RATIO GW9 OPTION CODE RING GEAR CODE RING GEAR CODE RING GEAR 6GA 7 50 6GB 7 50 2CY 8 50 6GM 7 50 GGN 7 50 2YH 8 50 3 08 RATIO GU4 OPTION 3 23 RATIO GU5 OPTION 3 42 RATIO GU6 OPTION CODE RING GEAR CODE RING GEAR CODE RING GEAR 8NC 8 50 2YE 8 50 2ZD 8 50 8DA 8 50 2YM 8 50 220 8 50 8LL 8 50 8LM 8 50 8BD 8 50 2ZA 8 50 2ZE 8 50 1991 GENERAL MOTORS SERVICE PARTS OPERATIONS CHEVROLET 17W 6 91 5 15 5 000