Power flow in 4th gear, function - GF27.10-P-3014SXA

TRANSMISSION 722.6 in MODEL 204.0, 216, 221 up to Model Year 8 

Fig 1: Identifying Sectional View Of Power Flow In 4Th Gear

Courtesy of MERCEDES-BENZ USA

Fig 2: Identifying 4Th Gear Power Flow Diagram

Courtesy of MERCEDES-BENZ USA

Principle of power transmission in 4th gear 

The direct gear ratio of 4th gear (i = 1) means that no torque or speed conversion takes place. The power is transmitted from the drive shaft (1) to the output shaft (5) via 3 locked planetary gear sets.

The following are not engaged:

• Multi-disk brake B1 (21)
• Multi-disk brake B2 (22)
• Multi-disk brake B3 (23)
• Freewheel F1 (27)
• Freewheel F2 (28)

Front planetary gear set 

The planet carrier (29/3) and sun gear (29/1) are permanently connected to each other via the engaged multi-disk clutch K1 (24). The planetary gear set is thus blocked and due to the mechanical connection between the ring gear (29/4) and drive shaft (1) rotates with input speed as a closed assembly.

Rear planetary gear set 

The multi-disk clutch K2 (25) is engaged and transmits the input speed of the drive shaft (1) via the ring gear (31/4) to the planet carrier (31/3). Via the mechanical connection to the locked front planetary gear set the ring gear (31/4) rotates at the same speed as the planet carrier (31/3). The planetary gear set is therefore locked and turns as a closed assembly.

Center planetary gear set 

Due to the engaged multi-disk clutch K2 (25) the ring gear rotates at input speed. The multi-disk clutch K3 (26) connects the sun gears of the center planetary gear set and rear planetary gear set. The equality of speeds of the ring gear (30/4) and sun gear (30/1) means that the planetary gear set is locked and rotates as a closed assembly.