Prowler V6-3.5L VIN G (1999)
Bell Housing: Testing and Inspection
NOISE
Defective or damaged bearings will normally produce a rough growl. This growl is constant in pitch and varies with the speed of the vehicle. Being
aware of this will enable a technician to properly diagnose bearing noise.
Transaxle bell housing input shaft bearing noise that results from defective or damaged bearings can usually be identified by its constant, rough sound.
The shaft front bearing noise is usually more pronounced during a coast condition. The shaft rear bearing noise is more pronounced during a drive
condition.
Bearing noise can best be detected by road testing the vehicle on a smooth road (black top). However, it is easy to mistake tire noise for bearing noise.
If a doubt exists, the tire treads should be examined for irregularities that often causes a noise that resembles bearing noise.
The most important part of service is correctly identifying the cause of failures and noise complaints. The cause of most failures is relatively easy to
identify. However the cause of noise is much more difficult to identify.
If vehicle noise becomes objectionable, isolate the noise to one area of the vehicle. Many noises that are reported as coming from one source may
actually originate at other sources. For example: tires, road surfaces, wheel bearings, engine, transmission, exhaust, or vehicle body. A thorough and
careful inspection should be completed to determine the actual source of the noise. This should be done before any disassembly and component
inspection is initiated.
The mounting bushings help to dampen-out noise when correctly installed. Inspect to confirm that no metal contact exists between the bell housing
case and the frame. Metal-to-metal contact can result in a noise. This noise could be eliminated if the components were correctly installed and
tightened. The complete isolation of noise to any one area requires considerable expertise and experience.
All bearings produce noise to a certain extent. Slight bearing noise at certain speeds or isolated situations are considered normal.
VIBRATION
Vibration at the rear of the vehicle is usually caused by a:
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Damaged drive shaft
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Worn, out-of-balance wheels
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Loose wheel lug nuts
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Loose/broken springs
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Damaged shaft bearings
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Damaged C/V joint
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Bent halfshaft
Check for loose or damaged front-end components or engine mounts. These components can contribute to what appears to be a rear-end vibration. Do
not overlook engine accessories, brackets and drive belts.
All driveline components should be examined before starting any repair. Refer to Steering and Suspension for additional information.
