Raise the vehicle and support it safely, then remove the exhaust system and exhaust heat shields. Mark the mounting flanges and driveshaft sections with paint to preserve the original orientation. At the front flex-disc, remove the three bolts holding the flex disc to the transfer case flange and discard the old fasteners. For 2007-2010 models, a dual stage flex disc is shown, while earlier models have a similar single stage flex disc. On 2004-2006 models, loosen the threaded clamping sleeve on the driveshaft a few turns. At the driveshaft rear universal joint, remove the Torx bolts at the differential input flange and discard them; if necessary, use a pry bar at the groove to free the universal joint. Hang the rear section of the driveshaft from the body using shift wire and remove the center support bearing mounting nuts. Pull down on the center of the driveshaft to remove it, using a pry bar if needed to free the flex disc from the centering dowel on the transfer case. Before installation, inspect the centering dowel on the transfer case output flange and the centering sleeve inside the driveshaft flex-disc, replacing any damaged components. When installing the centering sleeve over the centering dowel, apply a thin coat of molybdenum disulfide grease. Bend the driveshaft at the center universal joint for installation, aligning the match marks on the driveshaft with those on the differential and transfer case flanges. Using new ZNS fasteners, alternately tighten the bolts to draw the joint evenly into the flange, and once seated, tighten down the bolts. It is important not to reuse fasteners as they are designed for one-time use and to ensure the driveshaft is not left hanging unsupported. Finally, install the heat shields and exhaust system, then conduct a road test to check for noise or vibration.