For 1990-2009 cars

# VIB.DIAG. USING REED TACH. ROTATIONAL ORDER CHARTS

#### MODELS AFFECTED: 1986-1987 DE VILLE, FLEETWOOD, FLEETWOOD BROUGHAM, CIMARRON, AND 1987 ALLANTE

To aid in diagnosis of vibrations, Cadillac has developed rotatioanl 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 use of reed tachometers.This bulletin includes rotational order charts for the following vehicles:

1986 Cimarron with 2.0L Engine and Automatic Transaxle

1986 Cimarron with 2.0L Engine and Manual Transaxle

1986 Cimarron with 2.8L Engine and Automatic Transaxle

1986 Cimarron with 2.8L Engine and Manual Transaxle

1986 and 1987 De Ville and Fleetwood with Base Suspension

1986 and 1987 De Ville and Fleetwood with Touring Suspension

1986 and 1987 Eldorado and Seville

1986 and 1987 Fleetwood Brougham

1987 Fleetwood Brougham with Trailer Towing Package

1987 Allante

1987 Cimarron with Automatic Transaxle

1987 Cimarron 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.