Ford Mustang (1999-2004) Service Manual: Chuckle

Chuckle that occurs on the coast driving phase is usually caused by excessive clearance between the differential gear hub and the differential case bore.

Damage to a gear tooth on the coast side can cause a noise identical to a chuckle. A very small tooth nick or ridge on the edge of a tooth can cause the noise.

Clean the gear tooth nick or ridge with a small grinding wheel. If the damaged area is larger than 3.2 mm (1/8 inch), install a new gearset.

To check the ring gear and pinion, remove as much lubricant as possible from the gears with clean solvent. Wipe the gears dry or blow them dry with compressed air. Look for scored or damaged teeth.

Also look for cracks or other damage.

If either gear is scored or damaged badly, install a new ring gear and pinion.


If metal has broken loose, the axle housing must be cleaned to remove particles that will cause damage. At this time, any other new parts in the axle housing must also be installed, if necessary.

    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. ...

    Knock, which can occur on all driving phases, has several causes including damaged teeth or gearset. In most cases, one of the following conditions will occur: 1. A gear tooth damaged on the drive s ...

    Other materials:

    1. Remove the driveshaft (4602). For additional information, refer to Driveshaft in this section. 2. CAUTION: Under no circumstances is the driveshaft assembly to be clamped in the jaws of a vise or similar holding fixture. Denting or localizing fracture ca ...

    Parking Brake Control
    Removal 1. CAUTION: If any component in the parking brake system requires repair or if the rear axle housing (4010) is removed, the cable tension must be released. Place the parking brake control (2780) in the released position. 2. Remove the console. 3. ...

    Daytime Running Lamps (DRL) (Diagnosis and Testing)
    Refer to Wiring Diagrams Cell 97 , Daytime Running Lamps for schematic and connector information. Special Tool(s) 73III Automotive Meter or equivalent 105-R0057 Principles of Operation Daytime Running Lamps (DRL) The daytime running lamp ...