GM Service Manual Online
For 1990-2009 cars only

INFO. ON NEW PROM/MEMCAL IDENTIFICATION MARKINGS

SUBJECT: INFORMATION ON NEW PROM/MEMCAL IDENTIFICATION MARKINGS

MODELS: 1995 PRIOR PASSENGER CARS AND TRUCKS

************************************************************ NOTE: FOR THE PURPOSES OF THIS DOCUMENT, THE TERMS PROM AND MEMCAL WILL BE USED INTERCHANGEABLY.

TO SIMPLIFY IDENTIFICATION OF SERVICE PROMS, A NEW EXTERNAL MARKING FORMAT WILL BE IMPLEMENTED. PARTS MANUFACTURED AFTER SEPT 1994 WILL FEATURE THESE NEW MARKINGS. THIS CHANGE WILL PLACE THE FULL 8-DIGIT SERVICE PART NUMBER ON THE PROM, IN PLACE OF THE OLD 4-DIGIT "EXTERNAL ID" NUMBER. IN THE PAST, PARTS AND SERVICE PERSONNEL COULD NOT IDENTIFY A PROM WITHOUT USING A CROSS-REFERENCE TABLE THAT MATCHED EXTERNAL IDS AND SERVICE NUMBERS. IN THE FUTURE, THE CROSS-REFERENCE TABLE WILL NOT BE REQUIRED FOR PROMS; PARTS WILL BE ORDERED DIRECTLY FROM THE NUMBER APPEARING ON THE PROM. HOWEVER, THE LABEL WILL RETAIN THE BROADCAST CODE ALPHA CHARACTERS TO ALLOW CONTINUED USE OF CROSS- REFERENCE CHARTS, IF SO DESIRED.

OLD MARKING FORMAT: LINE LABEL MARKINGS EXPLANATION 1 "DELCO" IDENTIFIES DELCO AS MANUFACTURER 2 "ARCL" BROAD CAST CODE PART IDENTIFIER 3 "4625" "EXTERNAL ID" NUMBER

NEW MARKING FORMAT: LINE LABEL MARKINGS EXPLANATION 1 "ARCL" BROAD CAST CODE PART IDENTIFIER 2 "1613" FIRST FOUR DIGITS OF 8-DIGIT PART NUMBER 3 "4624" LAST FOUR DIGITS OF 8-DIGIT PART NUMBER

* ORDERING THE ABOVE PROM FROM THE OLD MARKING FORMAT WOULD REQUIRE USING A CROSS-REFERENCE CHART TO DETERMINE A SERVICE PART NUMBER, BASED ON THE BROAD CAST CODE AND EXTERNAL ID NUMBERS.

* TO ORDER FROM THE NEW FORMAT, SIMPLY COMBINE THE 2ND AND 3RD LINES TO FORM AN 8-DIGIT PART NUMBER THAT CAN BE DIRECTLY ORDERED FROM SPO (NUMBER 16134624 IN THE ABOVE EXAMPLE).

AS THESE CHANGES ARE PHASED INTO THE PARTS INVENTORY, IT SHOULD BE NOTED THAT DEALERS WILL CONTINUE TO SEE PARTS WITH BOTH FORMATS FOR SOME TIME IN THE FUTURE. THIS IS BECAUSE: - MILLIONS OF VEHICLES HAVE ALREADY BEEN BUILT WITH THE OLD FORMAT. - SPO HAS EXISTING STOCK OF MEMCALS AND PROMS WITH THE OLD FORMAT. - PROMS WITH 7-DIGIT PART NUMBERS (REPRESENTING LESS THAN 10% OF CURRENT PART NUMBERS) WILL CONTINUE TO USE THE OLD FORMAT. THE 7-DIGIT PART NUMBERS ARE EASILY IDENTIFIED BECAUSE THEY ALWAYS BEGIN WITH "122XXXX".

DUE TO MANUFACTURING PROCESSED, MORE THAN ONE 8-DIGIT PART NUMBER MAY APPEAR ON A MEMCAL. IN THIS EVENT, SERVICE PERSONNEL SHOULD USE THE LABEL ON THE EXTERIOR COVER OF THE MEMCAL ASSEMBLY. TO AVOID CONFUSION, ONLY THE SERVICE LABEL WILL INCLUDE THE BROAD CAST CODE, CONSISTING OF LETTER CHARACTERS (I.E., ARCL).

FIGURES: 1


Object Number: 78767  Size: FS

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.

COPYRIGHT 1994 GENERAL MOTORS CORPORATION. ALL RIGHTS RESERVED.