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Basic Function Of All-Wheel Drive With Automatic Transmission - GF28.00-P-1001A

Model all with transmission 725 

Model all with transmission 725 

with code M005 (Vehicles with 4MATIC/all-wheel drive) 

G14472121Courtesy of MERCEDES-BENZ USA

Schematic diagram of drive torque distribution 

Overview 

This document contains information on:

General 

The all-wheel drive on the automatic transmission is an drive type, which in contrast to front or rear wheel drive, routes the drive force of the combustion engine to all the wheels in contact with the ground. In all-wheel drive, a differentiation is made between permanent all-wheel drive and variable all-wheel drive.

Function 

Permanent all-wheel drive 

The drive torque of the combustion engine is distributed via the automatic transmission, to the flange-mounted transfer case (fixed drive torque distribution), and onwards to the front axle and rear axle differential.

Permanent all-wheel drive has a fixed torque distribution between the front and rear axle, with a pre-locking torque of 40 Nm. This basic concept allows high traction values.

The permanent all-wheel drive consists basically of the following components:

Variable all-wheel drive 

The drive torque of the combustion engine is distributed via the automatic transmission, to the flange-mounted transfer case (variable drive torque distribution), and onwards to the front axle and rear axle differential.

In the variable all-wheel drive, the drive torque at the front and rear axle can be shifted variably from 0-100 %. To do so, the drive torque is distributed by means of a clutch regulated electromechanically. The best possible torque distribution is calculated continuously to match the given driving situation and driver requests. The objective of variable all-wheel drive is to achieve a high traction along with increased lateral and longitudinal dynamics.

The variable all-wheel drive basically consists of the following components:

  Additional basic functions     
  Basic function of transfer case with front axle transmission output   GF28.10-P-1002A
  Basic function of front axle differential   GF33.30-P-1002A
  Electric differential lock basic function Model all with transmission 725
with code M005 (Vehicles with 4MATIC/all-wheel drive)
GF35.40-P-2001A
  Traction control, basic function   GF42.40-P-1001A
  Transfer case control unit, basic function Model all with transmission 725
with code M005 (Vehicles with 4MATIC/all-wheel drive)
GF28.19-P-9890A 
  Detailed information     
  All-wheel drive with automatic transmission, detailed information Model 167 with transmission 725.0
with code M005 (Vehicles with 4MATIC/all-wheel drive)
GF28.00-P-1002A
    Model 213, 238, 257 with transmission 725.0/1 as of model year 2021
with code M005 (Vehicles with 4MATIC/all-wheel drive)
GF28.00-P-1002B
    Model 232 with transmission 725.0/1
with code M005 (Vehicles with 4MATIC/all-wheel drive)
GF28.00-P-1002C
    Model 223 with transmission 725.0/1
with code M005 (Vehicles with 4MATIC/all-wheel drive)
GF28.00-P-1002D
    Model 206 with transmission 725
with code M005 (Vehicles with 4MATIC/all-wheel drive)
GF28.00-P-1002E
    Model 254 with transmission 725
with code M005 (Vehicles with 4MATIC/all-wheel drive)
 
    Model 290 with transmission 725
as of model year 2021
with code M005 (Vehicles with 4MATIC/all-wheel drive)
GF28.00-P-1002F