OEM 2009 GMC Yukon Crankshaft Seal

2009 GMC Yukon Crankshaft Seal Parts and Q&A

• Q: How to replace the front crankshaft seal (140) for exclusions RPOs LC9, LMG, LY2, and LY5 on 2009 GMC Yukon?

  A: The Crankshaft Front Oil Seal Installer (J 41478) serves as the necessary tool to replace crankshaft front oil seal (140) for all models outside of RPOs LC9, LMG, LY2, and LY5. Start the replacement procedure by disconnecting the crankshaft balancer. After removing the crankshaft front oil seal (140) from the front cover proceed with the next step. Oiling the oil seal sealing surface should be avoided as well as reusing the crankshaft front oil seal. Apply clean engine oil to both the outer portion of new oil seal (140) and bore of front cover oil seal surface. The crankshaft front oil seal (140) should be mounted onto the J 41478 guide before inserting the J 41478 threaded rod (along with nut, washer, and guide, and oil seal) into the crankshaft end. Follow these steps to install the oil seal into the cover bore using the J 41478 while applying one wrench to the hex on its installer bolt and the other wrench to turn its installer nut clockwise for complete seal insertion. Check that the front cover bore receives the complete and uniform installation of the oil seal after you take off J 41478. Finally, reinstall the crankshaft balancer.