For 1990-2009 cars

# POWER DOOR WINDOW TAPE DRIVE DISENGAGES

#### VEHICLES AFFECTED: 1986 OLDS AND BUICK 'C' AND 'H' 2-DOOR MODELS EQUIPPED WITH POWER WINDOW 1987 OLDS AND BUICK 'C' AND 'H' MODELS EQUIPPED WITH POWER WINDOWS

Late production 1986 door glass regulator assembly on two door models with power windows included an up stop. This expanded to all front door glass power regulators after October 1, 1986 on the 1987 'C' and 'H' models.

The added up stop prevents tape drive over travel and disengagement of the tape drive from the door glass. If a car has the above described condition and does not have an up stop, replace it with the later design. Part numbers and usage are indicated in the following chart:

POWER FRONT DOOR GLASS REGULATOR ASSEMBLY WITH UP STOP

PART NUMBER YEAR MODEL AND SIDE

20480596 1986 "H" 2-door - right 20480597 1986 "H" 2-door - left 20733072 1986 "C" 2-door - right 20733073 1986 "C" 2-door - left 20733070 1987 "H" and "C" 4-door - right 20733071 1987 "H" and "C" 4-door - left 20733074 1987 "H" and "C" 2-door - right 20733075 1987 "H" and "C" 2-door - left

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.