For 1990-2009 cars

# VIBRATION DIAGNOSIS-REED TACHOMETER & ROTATIONAL CHARTS

#### MODELS AFFECTED: 1988-1989 DE VILLES, FLEETWOODS, BROUGHAMS, STS SEVILLES, AND ALLANTES 1988 CIMARRONS

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.