Suburban 3/4 Ton 4WD V8-305 5.0L (1986)
PROM - Programmable Read Only Memory: Application and ID
PROM/MEMCAL Identification Marks
File In Section: 6E - Engine Fuel & Emission
Bulletin No.: 44-65-01
Date: October, 1994
Subject:
New PROM/MEMCAL Identification Markings
Models:
1995 and 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:
New Marking Format:
^
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 processes, 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).
