Drive/Propeller Shaft: Testing and Inspection

PROPELLER SHAFT

PROPELLER SHAFT VIBRATION

Out-of-round tires or wheels that are out of balance, will cause a low frequency vibration.

Driveline vibration can be from loose or damaged engine mounts.

Propeller shaft vibration increases with vehicle speed. A vibration within a specific speed is not usually caused by a out of balanced propeller shaft. Worn universal joints or an incorrect propeller shaft angle, usually cause such a vibration.

DRIVELINE VIBRATION






PROPELLER SHAFT BALANCE





NOTE: Removing and indexing the propeller shaft 180° relative to the yoke may eliminate some vibrations.

If propeller shaft is suspected of being out of balance, verify with the following procedure:

1. Place vehicle in neutral.
2. Raise and support the vehicle by the axles as level as possible.
3. Clean all foreign material from propeller shaft and universal joints.
4. Inspect propeller shaft for missing balance weights, broken welds, and bent areas.

NOTE: If propeller shaft is bent, it must be replaced.

5. Inspect universal joints for wear, properly installed and correct alignment with the shaft.
6. Check universal joint clamp screws torque.
7. Remove wheels and tires. Install wheel lug nuts to retain the brake drums/rotors.
8. Mark and number propeller shaft six inches from the pinion yoke end at four positions 90° apart.
9. Run and accelerate the vehicle until vibration occurs. Note intensity and speed the vibration occurred. Stop the engine.
10. Install a screw clamp (1) at position 1.

NOTE: If there is no difference in vibration at the other positions, the vibration may not be propeller shaft.

11. Start engine and re-check for vibration. If little or no change in vibration is evident, move clamp to the next positions and repeat vibration test.





12. If vibration decreased, install a second clamp and repeat vibration test.





13. If additional clamp causes additional vibration, separate clamps (1) 1/2 inch above and below the mark. Repeat the vibration test.
14. Increase distance between clamps and repeat test until vibration is at the lowest level. Bend the slack end of the clamps so the screws will not loosen.
15. If vibration remains unacceptable, preform the procedure to the front end of the propeller shaft.
16. Install the wheel and tires. Lower the vehicle.

PROPELLER SHAFT RUNOUT

1. Clean the propeller shaft surface where the dial indicator will contact the shaft.
2. The dial indicator must be installed perpendicular to the shaft surface.
3. Measure runout at the center and ends of the shaft away from weld areas, to ensure weld process will not effect the measurements.
4. Refer to Runout Specifications chart.
5. If propeller shaft is out of specification, remove propeller shaft and index the shaft 180°. Install the propeller shaft and measure shaft runout again.
6. If propeller shaft is now within specifications, mark shaft and yokes for proper orientation.
7. If propeller shaft runout is not within specifications, check runout of the transmission and axle. Correct as necessary and repeat propeller shaft runout measurement.
8. Replace propeller shaft if the runout still exceeds the limits.
RUNOUT SPECIFICATIONS