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:

Safety precautions
WARNING: Do not overfill the fuel tank. The pressure in an overfilled tank may cause leakage and lead to fuel spray and fire. WARNING: The fuel system may be under pressure. If you hear a hissing sound near the fuel filler inlet, do not refuel until the sound ...

Engine (Diagnosis and Testing)
Special Tool(s) Commercially Available Leakdown Tester Quick Disconnect Compression Tester 134-R0212 or equivalent Dial Indicator Gauge Adapter 303-007 (TOOL-6565-AB) or equivalent Dial Indicator Gauge with Holdin ...

Checking MyKey system status
You can find information about your programmed MyKeys by using the information display. MYKEY DISTANCE Tracks the distance when drivers use a MyKey. The only way to delete the accumulated distance is by using an admin key to clear your MyKey. If the distance ...