Some 1985-86 Devilles and Fleetwoods and 1986 Eldorados and Sevilles may experience a moan or buzzing noise accompanied by vibrations in the steering wheel, instrument panel, and floor pan. A second design vacuum pump and mounting bracket is installed after VIN number 281300 for 1986 FWD Devilles / Fleetwoods, 607957 for 1986 Eldorados, and 805741 for 1986 Sevilles, to provide additional vacuum pump isolation. The redesigned mounting system prevents the second design pumps being interchangeable directly with first. Since the first design pumps have been superseded by the second generation pump, it is necessary to install a new mounting bracket when replacing first design pumps. The second design part numbers are listed below.
PART NUMBER DESCRIPTION USEAGE
22062562 Vacuum Pump C, E, K 25527649 Bracket C 1633916 Bracket E, K 22055187 Grommets C, E, K
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.