Information on Mercedes-Benz - Automatic transmission 9G-TRONIC 725.0

The automatic transmission 9G-TRONIC 725.0 is an entirely
new electronically controlled automatic transmission with 9
forward gears and one reverse gear. The ratios for the gear
stages are achieved by planetary gear sets. All the transmis-
sion functions and control components for this automatic
transmission are combined in one assembly module. The fully
integrated transmission controller unit located in the automa-
tic transmission allows the number of interfaces to the wiring
harness in the vehicle to be minimized.
The use of the new fully integrated transmission con-
trol (VGS) system also provides the following additional
advantages:
• Good electromagnetic compatibility (avoidance of mutual
influence between various electronic components)
• Fast current control and compensation of fluctuations in
the on-board electrical system, resulting in increased shift
quality
• Precise determination of gearshift-relevant measurement
values and quicker evaluation of these measurement
values
An increased service life, reduced fuel consumption and ma-
ximum shift comfort are achieved through:
• A new transmission concept with 9 gears and a gear ratio
spread of 9
• New optimized transmission components
• Reduced working pressure
• The implementation of completely new software with ad-
ditional comfort and dynamic functions
• New actuator concept with two pumps
The transmission can be subdivided into the following
assemblies:
• Torque converter with torsional damper, centrifugal pen-
dulum and torque converter lockup clutch
• New oil pump (primary pump) with off-axis design for
generating the required oil pressure and for guaranteeing
lubrication of shift elements and bearing points
• Electric transmission oil pump for generating the requi-
red oil pressure and for guaranteeing lubrication of shift
elements and bearing points with the engine off and for
supporting the primary pump
• Transmission housing with mechanical transmission com-
ponents (planetary gear sets, electrohydraulically actua-
ted park pawl, multidisk clutches and multidisk brakes)
• Fully integrated transmission controller unit with integra-
ted fully integrated transmission control unit