Moan/Boom Noise

CONDITION:
Exhaust Moan/Boom 2300-2500 RPM range on 1991 vehicles with 3.4L engines (RPO LQ1) assembled prior to vehicle number MD360170.

CAUSE:
Exhaust system excited by engine exhaust pulse induced vibration.

CORRECTION:
Install exhaust damper, P/N 10199232. Reference Dealer Technical Bulletin 91-T-122.

All parts are currently available from GMSPO.