This is an information only bulletin. It has been noted that many Dealers are incorrectly using warranty labour operation K7700 when changing speedometer adapter assemblies (P/N 15618397) on S-Chassis Postal Vehicles. Labour operation K7700 should only be used when replacing the speedometer drive gear.
The proper labour operation for changing the speedometer adapter should be K6320. Use of the proper labour operations is very helpful to Engineering in diagnosing and eliminating product problems.
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.