Ford Kuga
Service Manual
Noise, Vibration and Harshness
Noise Diagnostic Procedure

Non-Axle Noise

The five most common sources of non-axle noise are exhaust, tires, roof racks, trim panels and transmission.

Therefore, make sure that none of the following conditions are the cause of the noise before proceeding with a driveline teardown and diagnosis.

In certain conditions, the pitch of the exhaust may sound very much like gear noise. At other times, it can be mistaken for a wheel bearing rumble.
Tires, especially snow tires, can have a high pitched tread whine or roar, similar to gear noise. Radial tires may have this characteristic.

Also, any non-standard tire with an unusual tread construction may emit a roar or whine noise.
Trim panels can also cause whistling or whining noise.
Clunk may be a metallic noise heard when the automatic transaxle is engaged in "R" (REVERSE) or "D" (DRIVE) or it may occur when the throttle is applied or released. It is caused by backlash somewhere in the driveline.
Bearing rumble sounds like marbles being tumbled. This condition is usually caused by a damaged wheel bearing.

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Noise, Vibration and Harshness (NVH)