To start, remove the splash shield under the transmission along with the intermediate muffler and heat shield. Remove the front and rear driveshafts, securing them to the side. For models with xDrive, remove the transmission and transfer case together and then detach the clutch. Inspect the flywheel for any scoring, hot spots, cracks, or loose or worn guide pins, and replace it if faults are found. For those N20 and N26 engines, lock the flywheel in position with the special tool. Then loosen and remove the mounting bolts with the next special tool. Finally clean the threads in the crankshaft for the mounting bolts. For NSS engines, the same flywheel removal procedure and tools can be used. Thread cleaning is also done. Before mounting the flywheel, check that the reluctor wheel is undamaged and positioned correctly, ensuring the dowel pin is in place. Additionally, check the installation of the flywheel location dowel sleeve for damage. Use new self-locking bolts to install the flywheel. Never re-use old stretch-type bolts. Never use thread-locking compound.