Operation CHARM: Car repair manuals for everyone.

A/T - Speed Sensor Ringing Noise at 42 to 45 MPH

Bulletin: 86-6-3

Date: Oct. '85

Ref. No.: 86-022-6
SUBJECT: "RINGING" NOISE AT 42 TO 45 MPH

MODELS AFFECTED: 1985-86 SOMERSET WITH 3.0L ENGINE (VIN CODE L)

Speed Sensor Heat Shield:




Some 1985-86 Somerset models built between January and September of 1985 may exhibit an audible "ringing" noise from the speed sensor heat shield located on top of the transaxle. This noise is dependent on engine speed, and it is most audible at vehicle speeds of 42 to 45 mph. This corresponds to 1,650 to 1,800 engine rpm with transaxle in 3rd gear and TCC on..

The cause of this condition is the speed sensor heat shield vibrating against the transaxle case. See Illustration.

Service Procedure:

Raise the car up on the hoist and looking from the underside of the transaxle, bend the speed sensor heat shield away from the transaxle case until the distance between the heat shield and the transaxle case is 5 mm (3/16"). After the heat shield has been bent away from the case, it should be visually checked to make sure the heat shield will not be contacting the exhaust manifold.