Driveshaft(s) – general information

1. A driveshaft is a tube that transmits power between the transmission or transfer case and the differential (s). Universal joints are located at either end of the driveshaft and allow the driveshaft to operate at different angles as the suspension moves.

2. Three different types of universal joints are used: single-cardan, double-cardan and constant velocity.

3. Some models have a two-piece driveshaft. The two driveshafts are connected at a center support bearing.

4. The rear driveshaft employs a splined yoke at the front, which slips into the exten­sion housing of the transmission. The front driveshaft on 4WD models (and the rear half of the driveshaft on models with a two-piece driveshaft) incorporates a slip yoke as part of the shaft. This arrangement allows the driveshaft to alter its length during vehicle operation. An oil seal prevents fluid from leak­ing out of the extension housing and keeps dirt from entering the transmission or transfer case. If leakage is evident at the front of the driveshaft, replace the extension housing oil seal (see Manual transmission Automatic transmission Transfer case ).

5. The driveshaft assembly requires very little service. Factory U-joints are lubricated for life and must be replaced if problems develop. The driveshaft must be removed from the vehicle for this procedure. Note: Some after-market universal joints have grease fittings to allow periodic lubrication.

6. Since the driveshaft is a balanced unit, it’s important that no undercoating, mud, etc. be allowed to accumulate on it. When the vehicle is raised for service it’s a good idea to clean the driveshaft and inspect it for any obvious damage. Also, make sure the small weights used to originally balance the driveshaft are in place and securely attached. Whenever the driveshaft is removed it must be reinstalled in the same relative position to preserve the balance.

7. Problems with the driveshaft are usually indicated by a noise or vibration while driv­ing the vehicle. A road test should verify if the problem is the driveshaft or another vehicle component. Refer to the Troubleshooting sec­tion at the front of this manual.