A potential noise compliance issue has been discovered on 1989 model 6.2L diesel engines. It is MANDATORY that these units have the timing reset PRIOR TO VEHICLE SALE to avoid potential noncompliance to federal, state, and local noise laws. Willfull violation of these laws can result in civil and/or criminal penalties. To correct this situation, the fuel injection pump timing must be reset on all affected units either in-stock or in-transit to your location PRIOR TO SALE of the vehicle.
ALL vehicles with GVW's over 10,000 lbs (K or J in the 4th position of the VIN) must be reset. Vehicles under 10,000 lbs GVW must be reset if they are to be sold in the following areas:
California Florida Maryland Nevada Oregon Washington Colorado
Cook County, Ehnois
Boston, MA Des Plains, IL Madison, WI Urbana, IL Chicago, IL Grand Rapids, MI Prairie Village, KS Washington, DC
The following VIN's represent the first engines reset by the assembly plants. Those vehicles (as well as those built after these VIN's) do not need to be reset by dealer personnel.
Assembly VIN Plant Product Breakpoint ----- ------- ---------- Flint Suburban/Utility KF 509934 GMC
Janesville R/V Crew Cab/ Cab Chassis KJ 504476 GMC
Pontiac East C/K Pick-Up/ Cab Chassis KE 511879 GMC
Oshawa C/K Pick-Up/ Cab Chassis K1 517743 GMC
Searborough G-Van/Cutaway Chassis K4 508355 GMC
Detroit Assembly P Model Chassis K3 501370 GMC
Use the following procedure in resetting the injection pump timing:
For noise compliance, fuel injection pump timing on all 1989 6.2L diesels is to be reset using the static timing procedure. The static timing marks, straight lines on the pump and front housing, must be aligned. The engine must be off while the timing is being set.
Static timing procedure:
Adjust: (Referenc eFigure 13, Page 6C2-9 in 1989 ------ Service Manual X8931 or X8932.)
Injection timing
* Loosen the three pump retaining nuts.
* Align the mark on the injection pump with the mark on the front cover (straight lines).
* Tighten pump retaining nuts to 40 Nm (30 lbs/ft)
Use Labor Operation J5965 and appropriate Labor Time when submitting a warranty claim for this procedure.
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.