INFORMATION ON CATALYTIC CONVERTER/MUFFLER PART NOS.. GMC Truck GMC MD Conventional (C Model) 1994

SUBJECT: INFORMATION ON CATALYTIC CONVERTER/MUFFLER PART NUMBERS

MODELS: 1994 CHEVROLET AND GMC TRUCK C6H, C7H, B7, AND P6 WITH CATERPILLAR 3116 DIESEL ENGINES (LXO) AND INTERIM DESIGN CHANGE (CTF)

MANY CHANGES HAVE BEEN MADE TO THE EXHAUST SYSTEM DUE TO CHANGES IN EMISSION LEGISLATION. STARTING FEBRUARY 1, 1994, NEW DIESEL EMISSION LAWS REQUIRED A NEW EXHAUST SYSTEM. SOME MEDIUM DUTY VEHICLES WITH 3116 CATERPILLAR DIESEL ENGINES REQUIRE AND ARE NOW EQUIPPED WITH CATALYTIC CONVERTERS INTEGRAL TO THE MUFFLER. ON APRIL 4, 1994 ANOTHER EXHAUST SYSTEM CONFIGURATION OCCURRED.

BELOW ARE REFERENCE TABLES LISTING EXHAUST SYSTEM CATALYTIC CONVERTER/MUFFLER AND MUFFLER REPLACEMENT PART NUMBERS AND RELATED OPTION CODES/DESCRIPTIONS FOR THE ABOVE SUBJECT MEDIUM DUTY VEHICLES EQUIPPED WITH VARIOUS ENGINE HORSEPOWERS AND EXHAUST SYSTEMS.

NOTICE: CATALYTIC CONVERTER/MUFFLERS ARE AVAILABLE THROUGH CATERPILLAR AND MUFFLERS WITHOUT INTEGRAL CONVERTERS ARE PROVIDED BY GMSPO.

REPLACEMENT PART NUMBER REFERENCE TABLES

VEHICLES BUILT BETWEEN 2-1-94 AND 4-3-94 WITH CTF

EXHAUST SYSTEM CATERPILLAR GM MUFFLER P/N OPTION CODES CONVERTER/MUFFLER P/N OPTION CODES OPTION CODE NRX NRZ/LVG

NPT 103-0634 15982888

NPY 103-0633 15982890

NB5 W/O GPG/NWD 103-0632 15982892

NB5/NC2 AND GPG/NWD 103-0635 15982889

VEHICLES BUILT 4-4-94 OR AFTER WITH CTF

EXHAUST SYSTEM CATERPILLAR GM MUFFLER P/N OPTION CODES CONVERTER/MUFFLER P/N OPTION CODES OPTION CODE NRX NRZ/LVG

NPT 103-0634 15982888 NPY 103-0633 15982890

NB5 (C7H064) ALL ENGINES OR C6H042/C7H042 103-0632 15982892 W/LVZ/LRU

NB5/NC2 (C6H042 OR C7H042) 103-0635 15982889 W/LVR/LVX/LVS/LVY

OPTION CODE REFERENCE TABLE

CTF INTERIM DESIGN CHANGE (REFER TO VEHICLE OPTION LABEL FOR VERIFICATION) GPG LOW PROFILE VEHICLE LVG EMISSIONS DELETE W/O CTF NB2 EMISSION SYSTEM, CALIFORNIA REQUIREMENTS NB5 EXHAUST SYSTEM, SINGLE NC2 TAILPIPE, SINGLE HORIZONTAL NPT EXHAUST SYSTEM, SINGLE HORIZONTAL MUFFLER, WITH VERTICAL TAILPIPE RH CAB MOUNT NPY EXHAUST SYSTEM, SINGLE HORIZONTAL MUFFLER, WITH VERTICAL TAILPIPE LH CAB MOUNT NRX EMISSION CONTROL DIESEL ENGINE EXHAUST NRZ EMISSION EQUIPMENT DIESEL ENGINES LESS CONVERTER NWD EXHAUST MODIFICATION, INCREASED GROUND CLEARANCE LVR 170 HP CAT 3116 DIESEL ENGINE LVX 185 HP CAT 3116 DIESEL ENGINE LVS 200 HP CAT 3116 DIESEL ENGINE LVY 215 HP CAT 3116 DIESEL ENGINE LVZ 250 HP CAT 3116 DIESEL ENGINE LRU 275 HP CAT 3116 DIESEL ENGINE

PARTS ORDERING INFORMATION:

ORDER INTEGRAL CATALYTIC CONVERTER/MUFFLERS FROM YOUR LOCAL CATERPILLAR DISTRIBUTOR. ORDER GM MUFFLERS WITHOUT CONVERTER FROM GMSPO.

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CAPTIONS:

GENERAL MOTORS BULLETINS ARE INTENDED FOR USE BY PROFESSIONAL TECHNICIANS, NOT A "DO-IT-YOURSELFER". THEY ARE WRITTEN TO INFORM THOSE TECHNICIANS OF CONDITIONS THAT MAY OCCUR ON SOME VEHICLES, OR TO PROVIDE INFORMATION THAT COULD ASSIST IN THE PROPER SERVICE OF A VEHICLE. PROPERLY TRAINED TECHNICIANS HAVE THE EQUIPMENT, TOOLS, SAFETY INSTRUCTIONS AND KNOW-HOW TO DO A JOB PROPERLY AND SAFELY. IF A CONDITION IS DESCRIBED, DO NOT ASSUME THAT THE BULLETIN APPLIES TO YOUR VEHICLE, OR THAT YOUR VEHICLE WILL HAVE THAT CONDITION. SEE A GENERAL MOTORS DEALER SERVICING YOUR BRAND OF GENERAL MOTORS VEHICLE FOR INFORMATION ON WHETHER YOUR VEHICLE MAY BENEFIT FROM THE INFORMATION.