Tools Required

J 38792-A Electronic Vibration Analyzer (EVA) 2

Notice: Do not fill the propeller shaft with foam, oil, or any other substance in order to correct a vibration. Filling the propeller shaft is only effective in reducing an unrelated condition called Torsional Rattle. Filling the propeller shaft should only be done in strict adherence to the procedure outlined in corporate bulletins that address Torsional Rattle. Failure to follow the correct procedure will induce a vibration and/or affect the structural integrity of the propeller shaft. The propeller shaft will then have to be replaced.

1. Support the vehicle on a hoist or jackstands. Support the axle(s) at curb height. Refer to Lifting and Jacking the Vehicle in General Information.
2. Turn the ignition ON.
3. Place the transmission in NEUTRAL.
4. Remove the rear tire/wheel assemblies. Refer to Tire and Wheel Removal and Installation in Tires and Wheels.
5. Remove the brake drums. Refer to Brake Drum Replacement in Drum Brakes.
6. Inspect the propeller shaft. The propeller shaft should be free of undercoating before continuing.

Notice: Do not depress the brake pedal with the brake rotors and/or the brake drums removed, or with the brake calipers repositioned away from the brake rotors, or damage to the brake system may result.

7. Start the engine.
8. Place the transmission in the highest forward gear.
9. Have an assistant accelerate and decelerate the vehicle through the speed range at which the vibration was first noted during the Vibration Analysis-Road Testing procedure.
10. Record whether the vibration was present, and at what speed.
11. If the vibration is present, determine which end of the driveshaft is vibrating the most. Hold an J 38792-A vibration sensor up to the pinion nose and the transmission tailshaft housing.
12. If the vehicle is equipped with a multiple-piece propeller shaft, hold an J 38792-A vibration sensor up to the center support bearing(s) to inspect for vibration.
13. If the transmission tailshaft housing is vibrating, hold the J 38792-A vibration sensor up to the transmission crossmember under the transmission mount. If there is no vibration on the crossmember, then the transmission mount is working properly.
14. Record which end of the driveshaft is vibrating the most, and how severe the vibration is. The inspection will be a reference by which to judge future progress.