MAIN BEARING USAGE CHART P/N SPECIFICATIONS

VEHICLES AFFECTED: ALL 1982-1988 4.1L AND 4.5L V-8 ENGINES

The chart below amends and updates the main bearing usage chart in Bulletin 87-641-102. This summary of main bearing applications is intended to clarify current bearing availability and to identify which bearings are in use on an engine being worked on. This information is not intended to supersede the GMSPO parts books and future parts catalog revisions. Superseded part numbers will be handled through GMSPO only, no further revisions to this bulletin are planned.

The procedure necessary to establish which bearing (standard or oversize) should be installed in the #1 or #5 positions, is contained in Bulletin 84-6-218 as well as 1987 and later Service Information Manuals. This procedure applies to all 1982-1988 4.1L and 4.5L V-8 engines.

Bearing Edge Service Parts Position # Application Color P/N* P/N ** Replaced By ---------- ----------- ----- ---- ------- ----------- 1 Original Production None 18006622 18009086 18012316 1 2nd Design Production Purple 18012275 18012316 18014329 1 3rd Design Production Red 18014079 18014329 1 Service Only O.S. (2nd Design) Blue 18012276 18012317 18014307 1 Service Only O.S. (3rd Design) Blue 18014306 18014307 3 Original Production None None 18009088 3634715 3 2nd Design Production None 1640033 3634715 2 & 4 Original Production None 18006622 18009086 18013442 2 & 4 2nd Design Production None 18013016 18013442 5 Original Production None None 18009087 18013793 5 2nd Design Production Pink 18013791U 18013793 18013789 18013792L 5 3rd Design Production Green 18013607 18013789 5 Service Only O.S. (2nd Design) Blue 18012876U 18012878 18013790 18012877L 5 Service Only O.S. (3rd Design) Black 18013608 18013790

(Parts in bold-face type are currently recommended)

* "Part Number" is number stamped on back of bearing shell. Use this number for identification.

** "Service Part Number" is number GMSPO assigns to part and prints on box. Use this number for ordering parts.

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.