Raise the vehicle and support it securely on jackstands. Drain the transaxle fluid if the filler plug is higher than the lowest part of the seal to prevent fluid loss during seal removal. Mark the rear driveshaft to transfer case yoke orientation, remove the driveshaft from the yoke and swing it out of the way. Remove the driveshaft at the rear axle and slide the driveshaft out of the transfer case extension housing. Hold the rear yoke with a suitable tool and remove the center retaining nut. Remove the yoke nut and washer. Remove the yoke and slinger from the transfer case rear output shaft. Remove early model non-flanged seals with a slide-hammer and adapter or carefully pry the seal out of the case bore with a blunt screwdriver. Remove later model flanged seals using a seal remover and slide hammer or tap out an edge of the seal using a dull screwdriver. Inspect the oil seal contact surface on the case for scoring or burrs and remove them with emery cloth or fine sandpaper. Apply multi-purpose grease to the oil seal and position it squarely into the case bore. Drive the seal squarely into the bore using an appropriately sized seal driver, large socket, or pipe section. Clean the yoke splines and lubricate lightly with multi-purpose grease, then slip the slinger and yoke over the output shaft and carefully past the new seal until it bottoms. Coat the face of the yoke retaining nut with RTV sealant and apply thread locking compound to the threads. Install the rubber seal, washer, and yoke retaining nut onto the output shaft. Tighten the retaining nut to the torque. Install the rear driveshaft. Check and refill the transfer case lubricant as necessary. Remove the jackstands and lower the vehicle. Shift out of 4WD and unlock hubs before returning the vehicle to normal service.