BASIC INFORMATION
ABOUT FOUR - WHEEL DRIVEPERMANENT 4WD
Permanent 4WD is a standard feature for M-Class. With permanent 4WD the driver does not need to make a decision to switch to 4WD because it is operative all the time. It is particularly suitable if the vehicle spends a lot of its time in difficult conditions. A full-time system allows 4WD power to be used on all surfaces. On-road performance is also enhanced by a permanent 4WD system.The M-Class has a front and rear differential with a central transfer case. Differentials transmit power to the drive wheels, while also allowing the wheels to rotate at different speeds when cornering. The central transfer case allows the front and rear propshafts to rotate at different speeds. The middle center differential ensures the necessary wheel speed equalisation between the axles and distributes the drive torque with a ratio of 50:50.
LOW RANGE
This 4WD mode offers maximum traction. Typically, it more than doubles the transfer case gear ratio, providing the vehicle with more torque and control in extreme conditions.ENGAGING LOW RANGE
With your M-Class at a standstill engage neutral (N). Thereafter engage the low range mode by pressing the rocker switch marked "LOW RANGE". The indicator light will flash twice and stay on indicating that you are in low range. The ESP mode MUST be disengaged because it is a high speed stability program. Press the rocker switch marked "ESP OFF". The indicator triangle on the instrument cluster will illuminate. Should you switch the vehicle off, ESP will automatically re-engage and before you proceed ESP must be disengaged again. Pressing the "LOW RANGE"-button automatically enables a special off-road ABS, so that the front wheels are cyclically braked at low speeds (below 30 km/h). This improves traction control in loose ground. Drivers must understand that locked wheels can slip and cannot be steered. The ESP also enters an off-road mode when the "LOW RANGE"-button is pressed. To disengage low range the vehicle must once again be in neutral and the procedure reversed.4-ETS
4-ETS is a unique M-Class feature that reduces driver error to allow maximum traction in all off-road driving conditions. The four-wheel Electronic Traction System (4-ETS), a microprocessor-controlled system, smoothly distributes the maximum allowable driving torque to the wheels with traction, while at the same time braking any slipping wheels.HOW 4-ETS WORKS
4-ETS uses the ABS wheel sensors to obtain information on individual wheel traction. If the wheels' speed sensors signal that one or more wheels have lost traction, the microprocessor automatically brakes the relevant wheel(s) using the ABS hydraulic unit. Thereby, the wheels with traction get the maximum allowable driving torque distribution, allowing for quick recovery of stable driving conditions.
HILL CLIMBING WITH 4-ETS
4-ETS allows the brake and accelerator pedal to be pressed simultaneously, allowing a driver to manage the demanding situation of ascending a steep, uphill track without rolling back when the vehicle is set in motion. This feature enables 4-ETS to become active while using the brake pedal. The system is automatically engaged when the vehicle starts moving and "LOW RANGE" is activated. Depending on the ground surface, the M-Class can handle gradients of up to 60 percent in low range. The system shuts itself off when each wheel exceeds a speed of 10 km/h.AUTOMATIC DOWNHILL BRAKE CONTROL
Automatic Downhill Brake Control, a standard feature on M-Class, maintains engine braking when a wheel loses traction while descending a steep decline. The system applies braking power automatically to the slipping wheel until traction is regained. Automatic Downhill Brake Control is automatically engaged with the Low Range function and operates within 3-20 km/h. Since Automatic Downhill Brake Control is an intrinsic technology, braking lights are not activated while Automatic Downhill Brake Control is operational. A driver's only indication that the Automatic Downhill Brake Control has been activated is the flashing of the 4-ETS control indicator light on the instrument cluster.TRACTION LOSS AND ACCELERATION
Uniform driving is important to maximise off-road capability. One unique feature of M-Class off-road operation is, that in the event of wheel spin and subsequent traction loss, acceleration must be increased proportionately to regain traction. This is different to other 4x4 operations where deceleration is required or recommended.APPROACH AND DEPARTURE ANGLES
The approach angle is the maximum angle at which you can approach an obstacle without touching your M-Class' front end. The departure angle is the maximum angle at which you can exit an obstacle without striking it. The approach angle on the M-Class is 26 degrees and the departure angle 25 degrees. That is enough for most slopes and steep gradients. With a factory-fitted towbar the departure angle is reduced 18.5 degrees when the towbar neck is in place (M-Class factory towbar feature removable neck pieces). The ML 55 AMG has an approach angle of 23 degrees and a departure angle of 21 degrees.STRADDLE ANGLE
The straddle angle is 20 degrees excluding the AMG which is 19 degrees. It is the maximum angle at which your M-Class can traverse an obstacle without striking or hanging up between axles.WADING DEPTH
The wading depth is 500 mm and should not be exceeded under any circumstances. Exceeding this depth can result in terminal engine damage.GROUND CLEARANCE
The maximum clearance between the lowest point of the M-Class and the ground measured on a flat surfaces is 204 mm and 189 mm for the AMG model.
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