For 1990-2009 cars

# 3.8L ENGINE DESIGN CHANGE HARMONIC BALL. TYPE

A LIMITED NUMBER OF BUICK "A" MODEL VEHICLES WILL BE EQUIPPED WITH BUICK 3.8 L ENGINES OF A DIFFERENT DESIGN FROM THE STANDARD PRODUCTION ENGINES. SHOULD AN ENGINE REPAIR BE ENCOUNTERED, THE DESIGNATED 3.8 L ENGINES CAN BE READILY IDENTIFIED EXTERNALLY BY THE HARMONIC BALANCER TYPE (SEE FIGURE 1). THE FOLLOWING PARTS LISTING WILL DIFFERENTIATE COMPONENT APPLICATION FOR SERVICE USE WITH RESPECT TO BOTH ENGINES. COMPONENT CYLINDER BLOCK STANDARD ENG. (3.8 L) 25506485 DESIGNATED ENGINE (3.8 L) 25506397 COMPONENT BALANCER - CRANK STANDARD ENG. (3.8 L) 25506570 DESIGNATED ENGINE (3.8 L) 25503832 COMPONENT FLYWHEEL ASM. STANDARD ENG. (3.8 L) 25508652 DESIGNATED ENGINE (3.8 L) 25501867 COMPONENT CONN. ROD ASM. STANDARD ENG. (3.8 L) 25506520 DESIGNATED ENGINE (3.8 L) 1255667 COMPONENT OIL PUMP CVR. & VLV. ASM. STANDARD ENG. (3.8 L) 965815 DESIGNATED ENGINE (3.8 L) 965708 COMPONENT MANIFOLD - INTAKE STANDARD ENG. (3.8 L) 25506510 DESIGNATED ENGINE (3.8 L) 25502702 COMPONENT MANIFOLD - EXHAUST - LT. STANDARD ENG. (3.8 L) 25507801 DESIGNATED ENGINE (3.8 L) 1263031 COMPONENT MANIFOLD - EXHAUST -RT. STANDARD ENG. (3.8 L) 25507782 DESIGNATED ENGINE (3.8 L) 25506381 COMPONENT SHIELD - EXHAUST MANIFOLD - LT. STANDARD ENG. (3.8 L) 25508523 DESIGNATED ENGINE (3.8 L) 25501883 COMPONENT SPARK PLUG STANDARD ENG. (3.8 L) 8990342 DESIGNATED ENGINE (3.8 L) 8990296

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.