Four-Wheel Drive (4WD) Vehicles

NOTE: If you remove an all-wheel-drive propeller shaft for diagnosis, it is recommended that you drive no more than needed (7 miles maximum). Additional mileage may damage the transfer case.

Important: Mark the propshafts (1) and the flange/yoke (2) before removing these components from the vehicle. Reinstall the prop shafts with the marks lined up in order to prevent induced vibrations.

1. If a vibration is sensitive to vehicle speed (mph), try removing either the front propshaft or the rear propshaft.
2. Install a plug in the opening for the transmission or the transfer case output shaft, in order to keep oil from leaking out.
3. Drive the vehicle through the vibration speed range.
4. If the vibration goes away with the propshaft removed, the problem is probably in that component.
5. If the vibration does not go away, put the propshaft back in. Remove the other propshaft. Repeat the road test.
6. If the vibration is still present, use an accurate reed tachometer or EVA in order to test the tire/wheel assembly or the related components (for example, the hub, the brake rotors, the drum). Remember, accurate vibration frequency readings are important.