Download ON-VEHICLE SERVICE If noise or vibration is present in the vehicle driveline, the driveshaft may be out of round due to damage. This inspection will help determine if the driveshaft and its attaching driveline components are “true” or turning with an absolute minimum amount of lateral movement. SPLINE BACKLASH Check for spline backlash by shaking driveshaft back and forth. LOOSE UNIVERSALS Check for loose universal yoke bolts and nuts. Tighten if necessary. DRIVESHAFT DEFLECTION 1. Place transmission in neutral. 2. Raise and support vehicle. 3. Install a dial indicator to the vehicle undercarriage and place the indicator plunger on the driveshaft. 4. Measure both shafts in three separate locations: At the center and 3 in (76.2 mm) from each yoke weld. Slowly turn one of the wheels to turn the driveshaft and record the highest indicator reading in all three locations. REMOVAL 1. Raise and support vehicle. 2. Place index marks (reference marks) on the driveshafts and their matching transfer case and differential input/output shafts.