System Components

System Components
Propeller Shaft








Steel, aluminum or hybrid propeller shafts are used corresponding to the type of engine/ gearbox combination installed. In the case of the hybrid propeller shafts, the front half of the shaft is made of steel and the rear half of the shaft is aluminum.
There are three different sizes (hole diameter of 96 and 105 mm) of the flexible coupling (1) used on the E60. The flexible coupling features a separate rubber bushing with a softer degree of rigidity. At very high torque, this rubber bushing is bridged by an internal stop.
The rigidity of the flexible coupling changes from soft to hard (as load is increased), thus protecting the soft rubber bush from overload or irreparable damage. The function is similar to that of a progressive spring.
The center bearing assembly is comprised of an aluminum bracket with integrated rubber fold-type seal.
The propeller shaft is equipped with a crash element that is located at the center bearing on the front section of the propeller shaft. In the event of an accident, the engine/gearbox unit or the rear axle is displaced, the bearing journal (3) is pressed into the propeller shaft (see item 1) specifically reducing the impact energy.





The bearing journal (3) serving as a mount for the crash element is made of steel.
The bearing journal is secured to the aluminum tube (2) by friction welding.
The two parts are spun into each other until the heat generated by the friction seizes them together.





The steel and hybrid propeller shafts are also pushed together (same as aluminum shafts) in the event of a crash.
The end of the front half of the steel and hybrid shafts is designed as a slip tube (1).
The slip tube (1) collapses if the engine/gearbox unit or the rear axle are displaced in the event of an accident.

Note: The crash element/slip tube of the propeller shafts may be deformed after an accident. If so, the propeller shaft must be replaced. After an accident, the propeller shafts must always be checked to establish whether the crash element/slip tube is pushed together (collapsed).

Final Drive (Rear Axle Differential)





Two different final drive sizes are used depending on the type of engine/gearbox combination is installed. The 6 cylinder models use the 1 88K and the 8 cylinder models use the 21 5K.
In the 188K, the gear ratio varies between 2.35 and 4.10 depending on the engine/gearbox combination.
In the 215K, the gear ratio varies between 2.47 and 3.46 depending on the engine/ gearbox combination.
The aluminum cover features cooling fins (1) to provide adequate cooling for the final drive. The cooling fins increase the surface area and therefore increase heat dissipation. This achieves a 7°C reduction in the oil temperature in the final drive. The final drive has a lifetime oil fill.

Output Shafts





Various output shafts are used on the E60, for example:
^ With the M54B30 engine, the constant velocity joints are the same size both at the wheel and final drive ends.
^ Manual transmission M54 vehicles are equipped with torsionally rigid output shafts to improve the load change characteristics. The torsionally rigid output shafts have a larger wall thickness and outside diameter than the standard rigid output shafts. This feature avoids drumming noises caused by torsional vibration.
^ M54 vehicles with automatic transmission are equipped with standard rigid output shafts.