LOW HEAT FROM HEATER (MODIFIED HEATER CORE)

INSUFFICIENT HEAT

Vehicles Affected: 1985-1988 M VANS -----------------

A new heater core to improve heater performance has been developed for 1985 - 1988 M Vans. The new heater core, P/N 52451085, has more fins per inch and will increase outlet temperatures up to four degrees fahrenheit.

The new core will fit into existing heater assemblies without any modifications. To install the new core, follow the instructions for heater core replacement found in Section 1A of M Van Service Manuals.

The new heater cores were incorporated into production beginning with the following VIN breakpoints:

CHEV - JB143302 GMC - JB511288

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.