To aid in diagnosis of vibrations, Cadillac has developed rotational order charts. These charts combined with resonant reed tachometer provide a systematic method for diagnosing vibration conditions. Refer to Serviceman Bulletin T-86-4, Group 0 for background and use of reed tachometers. This bulletin includes rotational order charts for the following vehicles:
1988-1989 DeVilles and Fleetwoods
1988-1989 Eldorados and Sevilles
1988-1989 STS Sevilles
1988-1989 Broughams
1988-1989 Broughams with Trailer Towing Package
1988-1989 Allantes
1988 Cimarrons with Automatic Transaxle
1988 Cimarrons with Manual Transaxle
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.