GENERAL INFORMATION PARTS BOOK CONTENT AND FORMAT THIS PARTS BOOK CONTAINS STANDARD RPO REGULAR PRODUCTION OPTION AND SEO SPECIAL EQUIPMENT OPTION PARTS AND IS ARRANGED IN THE FOLLOWING SEQUENCE DESCRIPTION PAGE MAJOR SECTION INDEX 4 4 1 GENERAL INFORMATION 44 4 4 2 METRIC CONVERSION TABLES 4 M 1 ABBREVIATIONS 4 T ABB 1 BASIC RPO SEO INDEX T 44 RPO 1 UPC GROUP INDEX UPC 1 CHARTS TEXT GROUPS O THRU 17 T 44 NUMERICAL ALPHABETICAL INDEXES PARTS BOOK CONTENT AND FORMAT THE MAJOR SECTION INDEX ON PAGE 1 TELLS YOU THAT IN THIS PARTS BOOK MAJOR SECTION 1 COVERS FRONT AXLE PARTS SECTION 4 COVERS BRAKE PARTS ETC THE SECTION 1 FRONT AXLE SECTION OF THIS BOOK IS THEN NUMBERED AS 1 1 1 2 ETC SECTION 4 WOULD BE 4 1 4 2 AND SO ON AT THE FRONT OF EACH SECTION IS A SUBGROUP INDEX ALSO ON THE FIRST PAGE OF EACH SECTION IS PRINTED A BLACK TAB THAT LINES UP WITH THE SECTION REFERENCE IN THE SECTION INDEX IN THE FRONT OF THE BOOK BY SLIGHTLY BENDING THE BOOK SO THAT THE PAGES FAN OUT YOU CAN QUICKLY SEE THESE TABS WHICH ARE INTENDED FOR QUICK REFERENCE TO SPEED UP THE LOCATION OF ANY PARTICULAR SECTION THE TEXT PORTION OF SOME MAJOR SECTIONS START WITH A LISTING OF THE MAJOR ASSEMBLY PART NUMBERS WHETHER OR NOT THE ASSEMBLY ITSELF IS STOCKED AND OFFERED FOR SERVICE IS SO INDICATED IN THE QUANTITY COLUMNS PRECEDING THE PART NUMBER EVEN WHEN NOT STOCKED FOR SERVICE COMPLETE ASSEMBLIES CAN NORMALLY BE PURCHASED IF THEY ARE STILL IN CURRENT PRODUCTION EACH MAJOR SECTION SECTION 1 FRONT AXLE SECTION 2 REAR AXLE ETC IS DIVIDED INTO SUB GROUPS OF RELATED PARTS EACH SUBGROUP DEALS WITH ONE SPECIFIC TYPE OF PART SUCH AS 2 0170 REAR AXLE SHAFT 2 0220 AXLE GASKET ETC SUBGROUPS ARE ARRANGED ALPHABETICALLY IN GROUP NUMBER ORDER EXCEPT FOR THE MAIN SUBGROUP PART AND THE KITS WHICH WILL NORMALLY BE LISTED FIRST PARTS BOOK INDEXES IN ADDITION TO THE MASTER SECTION INDEX THAT APPEARS ON THE 1ST PAGE OF THE BOOK AND THE SUBGROUP INDEXES THAT PRECEDE EACH GROUP THERE ARE TWO OTHER INDEXES PROVIDED FOR YOUR CONVENIENCE THEY ARE ALPHABETICAL INDEX LISTS EACH PART COVERED IN THE BOOK IN ALPHABETICAL ORDER AND LISTS THE APPLICABLE U GROUP NUMBER NUMERICAL INDEX LISTS EACH PART COVERED IN THE BOOK IN NUMERICAL ORDER AND THEN LISTS THE APPLICABLE GROUP NUMBERS GROUP CONVERSION INDEX TO ASSIST USERS FAMILIAR WITH THE WDDGM GROUPING TO DETERMINE THE COMPARABLE GMC GROUP NUMBER PARTS IDENTIFICATION AIDES OTHER IMPORTANT AIDS TO PROPER PARTS IDENTIFICATION APPEAR IN THE GENERAL INFORMATION SECTION OF THIS BOOK THEY ARE INFORMATION ON HOW TO LOCATE PARTS WITHIN THIS PARTS BOOK PARTS BOOK PAGE FORMAT AND MODEL USAGE TERMS A DESCRIPTION OF WHAT EACH CHARACTER MEANS IN THE VEHICLE IDENTIFICATION NUMBER AN EXPLANATION OF WERE TO LOOK IN A VEHICLE TO FIND SPECIAL INFORMATION THAT IS NECESSARY FOR PROPER PARTS IDENTIFICATION TRUCK SERIES OPTIONAL EQUIPMENT LISTINGS BY MODEL NUMBER A COMPLETE LISTING OF ABBREVIATIONS USED THROUGHOUT THE PARTS BOOK A BASIC RPO INDEX IN RPO ALPHA NUMERIC ORDER AND A WORD DESCRIPTION O 1987 GENERAL MOTORS SERVICE PARTS OPERATIONS M SB 2