This procedure applies only to NVG-900
Transfer Cases, as the output shaft seal on MJ-8 transfer cases is not normally serviced. Begin by raising the vehicle and securely supporting it on jackstands. Drain the transfer case lubricant, then remove the driveshaft. Mark the relative positions of the pinion, nut, and flange. Use a beam-or dial-type inch-pound torque wrench to determine the torque required to rotate the pinion and record it for later use. Count the number of threads visible between the end of the nut and the end of the pinion shaft, and record that as well. Remove the flange mounting nut using a chain wrench to hold the pinion flange while loosening the locknut. A small puller will be required to remove the companion flange, ensuring it has two bolts that screw into the companion flange. Pry out the seal with a screwdriver or seal removal tool, taking care not to damage the seal bore. Lubricate the lips of the new seal with multi-purpose grease and tap it evenly into position with a seal installation tool or a large socket, ensuring it enters the housing squarely and is tapped to its full depth. Align the mating marks made before disassembly and install the companion flange, tightening the pinion nut if necessary to draw the flange into place. Carefully tighten the nut until the original number of threads are exposed and the marks are aligned. Measure the torque required to rotate the pinion and tighten the nut in small increments until it matches the recorded figure. Finally, connect the driveshaft, add the specified lubricant to the transfer case, and lower the vehicle.