Ford Mustang (1999-2004) Service Manual: Gear Howl and Whine

Howling or whining of the ring gear and pinion is due to an incorrect gear pattern, gear damage or incorrect bearing preload.

Wheel Hub or Axle Flange Face Runout
NOTE: If the axle shaft assembly is removed, check runout of the shaft itself. The forged (unmachined) part of the shaft is allowed to have as much as 3.0 mm (0.120 inch) runout. This alone will not ...

Bearing Whine
Bearing whine is a high-pitched sound similar to a whistle. It is usually caused by worn/damaged pinion bearings, which are operating at driveshaft speed. Bearing noise occurs at all driving speeds. ...

Other materials:

Pinpoint Tests
CAUTION: Before removing and installing the GEM or its connectors, disconnect the battery. Failure to follow this caution will result in the GEM storing many erroneous DTCs and it may exhibit erratic operation after installation. CAUTION: Be careful when pr ...

Inspection and Verification
1. Verify the customer concern by operating the engine to duplicate the condition. 2. Visually inspect for obvious signs of mechanical damage. Refer to the following chart. Visual Inspection Chart Mechanical Engine coolant leaks ...

Symptom Chart
Condition Possible Sources Action The Brakes Pull or Drift Tire air pressure. Wheel alignment. Brake pads. Brake components. Suspension component. Go To Pinpoint Test A . ...