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For 1990-2009 cars only

MANUAL TRANSMISSION NEUTRAL IDLE GEAR RATTLE

Models 1984-89 FIREBIRD WITH 2.8L Affected: (VIN CODE S - 1985-89, VIN CODE 1 - 1984)

Some 1984-88 and early built 1989 Firebird models equipped with V-6 engines and manual transmissions may exhibit a "rattle" type noise with the transmission in neutral and engine at idle. On vehicles with this type of noise the following procedure should be used to verify that the noise is transmission neutral gear "rattle."

1. Place the vehicle on a level surface with the parking brake set, and check the transmission fluid level and shift boot condition.

2. With the engine at idle and transmission in neutral (at normal operating temperature) fully depress the clutch pedal and listen for the noise. If the noise disappears then the noise is most likely neutral gear "rattle." If the noise doesn't disappear, then the source of the noise is likely to be engine related.

If neutral idle gear "rattle" is present it may be eliminated by installing a new clutch driven disc assembly, P/N 10079751 which incorporates an additional neutral damper device.

Parts are expected to be available on January 9, 1989. Until then normal part orders will not be accepted by GMSPO. Only verifiable emergency VIP orders will be accepted. GMSPO will make every effort to obtain parts. All parts will be placed on 400 control to waive VIP surcharges. However, the part will be shipped premium transportation at dealer's expense. All other order types will be canceled as incorrectly ordered while the 400 control is in place.

Use applicable Labor Operation Number and Labor Time.

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.