PRINCIPLE OF OPERATION
For a detailed description of the driveline system and operation, refer to the relevant Description and Operation instructions. Refer to Driveshaft , Universal Joints , Rear Drive Axle and Differential , Front Drive Axle and Differential , Front Drive Halfshafts , Halfshaft Joint and Rear Drive Halfshafts .
INSPECTION AND VERIFICATION
| CAUTION | Diagnosis by substitution from a donor vehicle is NOT acceptable. Substitution of control modules does not guarantee confirmation of a fault, and may also cause additional faults in the vehicle being tested and/or the donor vehicle. |
Note. Check and rectify basic faults before beginning diagnostic routines involving pinpoint tests.
- Verify the customer concern. If a road test is necessary make sure the vehicle is safe to do so.
- Visually inspect for obvious signs of mechanical damage. VISUAL INSPECTION Mechanical Wheel rim and tire damage or runout Check all the driveshafts and halfshafts for damage including dents, cracks and excessive runout Check all the CV joint gaiters for splits, damage and security Check all the driveshafts and halfshafts for correct alignment Check the driveshaft mounting bolts security Check all the driveshaft and halfshaft joints for excessive movement Check the rear driveshaft center support bearing for security, damage and excessive wear Check the front and rear differential mounting bolts and bushes for wear, damage and security Check the front and rear differentials for oil leaks
- If an obvious cause for an observed or reported concern is found, correct the cause (if possible) before proceeding to the next step.
- If the cause is not visually evident, verify the symptom and refer to the Symptom Chart, alternatively check for Diagnostic Trouble Codes (DTCs) and refer to the DTC Index.
SYMPTOM CHART
| Symptom | Possible Causes | Action |
|---|---|---|
| Vibration through the vehicle body at a specified speed | Road wheel imbalance Driveshaft imbalance | Road test the vehicle. If the vibration is only at a specified speed, balance the road wheels. Test for normal operation. Disconnect the rear driveshaft. Check CV and universal joints for smooth and full movement. Disconnect the front driveshaft. Check CV joints for smooth and full movement. If any joints are faulty, replace the driveshaft. Test for normal operation. |
| Vibration through the vehicle body at all speeds | Misalignment of the rear driveshaft Bent or misaligned stub axle | Road test the vehicle. Check the rear driveshaft for correct alignment through the center support bearing. Rectify as necessary. Test for normal operation. Check for a damaged or bent stub axle. Rectify as necessary. |
| Rumbling noise from the rear of the vehicle varying at different vehicle speed and load | Rear differential bearings worn Rear wheel bearings worn Rear driveshaft center support bearing worn | Using a suitable listening device (e.g. stethoscope) listen to the rear differential pinion bearings and output bearings, the rear wheel bearings and the rear driveshaft center bearing. Rectify as necessary. Test for normal operation. |
| Rumbling noise from the front of the vehicle varying at different vehicle speed and load | Front differential bearings worn Front wheel bearings worn | Using a suitable listening device (e.g. stethoscope) listen to the front differential pinion bearings and output bearings and the front wheel bearings. Rectify as necessary. Test for normal operation. |
| Whining noise from the rear of the vehicle during acceleration and overrun conditions | Rear differential gears worn or damaged | Check and top up the rear differential oil level if necessary. Using a suitable listening device (e.g. stethoscope) listen to the rear differential. Replace the rear differential unit if there is excessive gear noise. |
| Whining noise from the front of the vehicle during acceleration and overrun conditions | Front differential gears worn or damaged | Check and top up the front differential oil level if necessary. Using a suitable listening device (e.g. stethoscope) listen to the front differential. Replace the front differential unit if there is excessive gear noise. |
| Knocking, clicking or clunking noise from rear of vehicle during acceleration and overrun conditions | Rear driveshaft joint fixings insecure Rear driveshaft joints worn or damaged Rear halfshaft joints or splined shaft worn or damaged Rear differential internal components worn or damaged | Disconnect the rear driveshaft. Check joint mounting bolt holes for elongation. Check the joints. Disconnect the rear halfshafts. Check the shaft splines for wear or damage. Check the CV joints. Rectify as necessary. With the rear driveshaft and halfshafts disconnected, check the rear differential for tight spots or excessive play. Rectify as necessary. |
| Knocking, clicking or clunking noise from front of vehicle during acceleration and overrun conditions | Front driveshaft CV joints worn or damaged Front halfshaft joints or splined shaft worn or damaged Front differential internal components worn or damaged | Disconnect the front driveshaft. Check joint mounting bolt holes for elongation. Check the joints. Disconnect the front halfshafts. Check the shaft splines for wear or damage. Check the CV joints. Rectify as necessary. With the front driveshaft and halfshafts disconnected check the front differential for tight spots or excessive play. Rectify as necessary. |
DTC INDEX
For a list of Diagnostic Trouble Codes (DTCs) that could be logged on this vehicle, please refer to the appropriate article.