Depending on the transmission that is installed, there is a slight variance in automatic transition removal. When removing an AWD vehicle transmission, the xDrive transfer case will remain attached. Detach the battery's negative cable and lift up the truck; support it safely, and remove the splash shields and supporting brackets under the engine and transmission. The chassis reinforcement plate has to be dismantled for AWD vehicles, likewise the exhaust system and heat shields. In the case of xDrive models, the front drive shaft is removed from the car. As to the rear driveshaft, support the center and remove the flex-disc from the transfer case. Don't let the driveshaft hang unsupported. On the right-hand side of the transmission, take off the fastener and the grounding strap, then the heat shield and bracket on both sides. Be prepared to catch transmission fluid and be sure to change O-rings on the line after disconnecting transmission cooler lines. For N20 and N26 engines, remove the support between the transmission and catalytic converter. For N55 engines, remove the corresponding nuts and fasteners. In order to reach the torque converter fasteners, the engine is hand cranked. The special tool locks the torque converter in place. Using a hoist, support the transmission, remove bolts and nuts, disconnect the electrical connector from the transfer case control unit, and release the mechatronics electrical connector. Take out any remaining bolts that secure the transmission bell housing. With the transmission bell housing unfastened, carefully pull the transmission back and down while ensuring no lines or wires are snagged. Examine the engine drive plate and flywheel for damage and replace as necessary. To properly install the transmission, make sure that the torque converter is seated correctly, replace all the aluminum fasteners and tighten to specified torque. The rest of the installation is carried out in the reverse order of removal, including the installation of new sealing washers or O-rings on ATF cooling line fittings, adjustment of the gearshift mechanism, and topping-up the transmission with clean ATF.