To remove the rear differential assembly, first raise the rear of the vehicle and securely support it on jackstands, blocking the front wheels to prevent rolling, and place the transmission in Neutral with the parking brake off. Mark the relationship of the driveshaft to the pinion flange, then unbolt the driveshaft from the flange and suspend it with a piece of wire. Using a hammer and a punch, unstake the pinion flange nut and mark the position of the pinion nut to the flange and the flange to the pinion shaft with dabs of paint. If available, use a beam-type inch-pound torque wrench to measure the pinion bearing drag and record the reading for later reference. A flange holding tool or chain wrench will be needed to keep the companion flange from moving while loosening the self-locking pinion nut, which should then be removed. Withdraw the flange, using a two-jaw puller if necessary, and avoid prying or hammering behind the flange or on the end of the pinion shaft. Pry out and discard the old seal using a seal removal tool or a large screwdriver, taking care not to disturb the pinion. For installation, lubricate the lips of the new seal and fill the space between the seal lips with wheel bearing grease, then tap it evenly into position with a seal installation tool or a large socket, ensuring it enters the housing squarely and to its full depth. Install the pinion flange and tighten the pinion nut to draw the flange into place without hammering it, aligning the previously made paint marks or reaching the original bearing preload as measured by the torque wrench. Finally, reconnect the driveshaft to the pinion flange and check the differential lubricant level, adding as necessary to reach the appropriate level.