NEW DESIGN CYL. HEAD GASKETS 90 DEGREE 'V' ENGINES

VEHICLES AFFECTED: 1987 AND PAST MODEL YEAR PASSENGER AND TRUCK VEHICLES EQUIPPED WITH 4.3L, 5.0L AND 5.7L 90 DEGREE V ENGINES

An improved cylinder head gasket of composite construction has been released to replace the metal gasket. The new gasket has improved sealing capabilities. The new part numbers shown below should be used for service.

Application Cvlinder Head Gasket

4.3L Passenger and Truck 10066080 5.OL Passenger and Truck 10066081 5.7L Passenger and Truck 10066082

Engines manufactured after the following build dates should have the composite gasket.

Engine Build Date Engine Build Code

4.3L May 15, 1987 T0515XXX

5.OL July 1, 1987 V070lXXX K0701XXX 5.7L July 1, 1987 V0701XXX K0701XXX

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.