WHISTLING NOISE AT IDLE SPEED THM 180C/REPLACE WEAR PLATE

MODELS AFFECTED: 1982 & 1983 CHEVETTES AND PONTIAC T-1000'S BUILT WITH THM 180C TRANSMISSION THE VEHICLES REFERENCED ABOVE MAY EXHIBIT THE FOLLOWING CONDITION: HIGH PITCHED WHISTLING NOISE-OCCURRING IN REVERSE, DRIVE, AND MANUAL LO WITH THE ENGINE WARM TO HOT. THE NOISE WHICH IS ONLY HEARD AT ENGINE IDLE SPEEDS SOUNDS LIKE A WHISTLING TEA KETTLE. -DO NOT-CONFUSE THIS WHISTLE NOISE WITH PUMP WHINE OR CAVITATION WHICH CAN BE CAUSED BY EITHER A PLUGGED OIL FILTER OR LEAKING OIL FILTER GASKET. THIS WHISTLING NOISE, IF FOUND, IS COMING FROM THE CONVERTER FEED HOLE LOCATED IN THE OIL PUMP WEAR PLATE. TO ELIMINATE THIS WHISTLING NOISE, OBTAIN A NEW OIL PUMP WEAR PLATE, PART NUMBER 96013212, FROM W.D.D.G.M. AND INSTALL IT. IF THE OIL PUMP WEAR PLATE IS OBTAINED FROM DEALERSHIP STOCK RATHER THAN FROM W.D.D.G.M., CHECK THE SURFACE FINISH PRIOR TO INSTALLING THE PART. IF THE SURFACE OF THE PART IS BRIGHT OR SHINY WITH WIRE BRUSH OR GRIND MARKS RUNNING IN ONE DIRECTION ACROSS THE SURFACE - DO NOT-USE THE PART!!! IT MAY RESULT IN A REOCCURANCE OF THE NOISE CONDITION. IF THE SURFACE IS DULL WITH MANY SMALL MARKS IN AN IRREGULAR PATTERN THE PARK IS OK TO USE. WHEN REASSEMBLING THE TRANSMISSION FOLLOW THE STEPS SHOWN IN YOUR SERVICE MANUAL AND BE CERTAIN TO USE THE CONVERTER TO OIL PUMP ALIGNMENT TOOL J-23082-01.

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.