Nissan 12279-4Z001 Rear Main Seal

Remove the transmission. Remove the flywheel/driveplate. Remove the rear Crankshaft Seal retainer from the block by unbolting the rear Crankshaft Seal retainer from the engine block and oil pan. Scrape any sealant or gasket material from the retainer, oil pan and the block. Position the seal and retainer assembly between two wood blocks, to evenly support the aluminum housing, and drive the old seal out with a hammer and punch. A screwdriver can also be used to pry the seal out, being careful not to gouge or nick the housing during seal removal. Place the new seal squarely on the retainer and drive it into the retainer with a wood block or a section of pipe slightly smaller in diameter than the outside diameter of the seal. Lubricate the crankshaft seal journal and the lip of the new seal with multi-purpose grease. Apply a continuous 1/8-inch bead of RTV sealant around the perimeter of the seal retainer. Also apply sealant to the bottom of the retainer (oil pan mating surface). Slowly and carefully push the seal onto the crankshaft. The seal lip is stiff, so work it onto the crankshaft with a smooth object such as the end of a socket extension as you push the retainer against the block. Install and tighten the retainer bolts securely. The remaining steps are the reverse of removal.