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:

Removal
CAUTION: Suspension fasteners are critical parts because they affect performance of vital components and systems and their failure can result in major service expense. A new part with the same part number must be installed if installation becomes necessary. ...

Rear Drive Halfshafts (Description and Operation)
The rear wheel drive halfshaft system consists of and operates as follows: Halfshafts (4K138) transmit engine torque from the rear axle housing to the rear wheels. Halfshafts rotate at approximately one-third the speed of a driveshaft and do not cont ...

Transmission (Disassembly)
Special Tool(s) Remover, Mainshaft Bearing 308-058 (T77J-7025-H) Screw, Bearing Removal tube 308-092 (T84T-7025-B) Holding Fixture, Transmission 307-003 (T57L-500-B) Remover, Bushing 307-001 (TOOL-1175-AC) ...