Mercedes-Benz ML320. Manual — part 155

Fig. 42: Command Valve, Function
Courtesy of MERCEDES-BENZ OF NORTH AMERICA.

Operation

When the end face is unpressurized (stationary phase), the working pressure is directed to the actuated shift
element. If the end face of the command valve (31) is subjected to shift valve pressure (p-SV) (shift phase), then
the shift pressure (p-S) is switched to the engaging element and the overlap pressure (p-U) is switched tot he
disengaging element. See Fig. 42.

Multiple-Disc Brake, Location/Task/Design/Function

Fig. 43: Multiple-Disc Brake

2001 Mercedes-Benz ML320

1998-03 AUTOMATIC TRANSMISSIONS Complete Transmissions - ML 320 - 722.662

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Courtesy of MERCEDES-BENZ OF NORTH AMERICA.

Multiple-Disc Brake, Location

Three multiple-disc brakes arranged as the front, center and rear multiple-disc brake (B1, B3, B2) are
located in the planetary gear sets in the transmission housing. See Fig. 43.

Multiple-Disc Brake, Task

Brace the ring gear, sun gear or planet carrier of a planetary gear set against the transmission housing in
order to transmit the drive torque.

Multiple-Disc Brake, Design

A multiple-disc brake consists of a number of internally toothed discs (10) on an internally toothed disc
carrier and externally toothed discs (9) on an externally toothed disc carrier, which is rigidly connected to
the transmission housing.

Multiple-Disc Brake, Function

See MULTIPLE-DISC BRAKE, FUNCTION.

Multiple-Disc Brake, Function

2001 Mercedes-Benz ML320

1998-03 AUTOMATIC TRANSMISSIONS Complete Transmissions - ML 320 - 722.662

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Fig. 44: Mulitple-Disc Brake, Function
Courtesy of MERCEDES-BENZ OF NORTH AMERICA.

2001 Mercedes-Benz ML320

1998-03 AUTOMATIC TRANSMISSIONS Complete Transmissions - ML 320 - 722.662

me

Operation

If the piston (B1a) on multiple-disc brake B1 is subjected to oil pressure, it presses the internal and external
discs of the disc set together. See Fig. 44. The front sun gear (v1) on the housing is locked via the internal
multiple-disc carrier (B1c). the front planetary gears (V2) roll on the front sun gear (V1).

If the rear multiple-disc brake (B2) is engaged via the piston (B2a), then this presses the disc set together. The
center sun gear (M1) is locked against the housing via the internal multiple-disc carrier (B2c). The center
planetary gears (m2) roll on the center sun gear (M1).

If the center multiple disc brake (B3) is engaged via the piston (B3a), then the rear planetary gear carrier (H3)
and the center hollow gear (M4) are locked. When the center multiple-disc brake (B3) is engaged the direction
of rotation reverses.

Multi-Plate Clutch, Location/Task/Design/Function

2001 Mercedes-Benz ML320

1998-03 AUTOMATIC TRANSMISSIONS Complete Transmissions - ML 320 - 722.662

me