Pull away slowly when the differential locks are activated.

Function or performance tests may only be performed on a 2-axle dynamometer. If you wish to operate the vehicle on such a dynamometer, please consult an authorized Mercedes-Benz Center beforehand. You could otherwise damage the drive train or the brake system.

Automatic mode

Use automatic mode 2 for all driving situations, including driving off-road or when fording.

In automatic mode, the differential locks are engaged and disengaged according to driving requirements. This guarantees sufficient traction for most driving situations with unrestricted vehicle steerability.

► Start the engine.

The differential locks are in automatic mode. The indicator lamp in selector wheel 1 lights up above symbol for automatic mode 2.

Engaging manually

WARNING  
Never drive on a paved surface with the center and rear axle differential locks manually engaged. Ability to steer the vehicle is greatly reduced when the differential locks are manually engaged, increasing the risk of an accident.
For safety reasons, the locks are automatically released at a vehicle speed above 31 mph (50 km/h). Nevertheless, you should only manually lock the differential if absolutely necessary because engaged locks will restrict the vehicle drivetrain while cornering and cause the vehicle to chatter.
This could cause you to lose control of the vehicle and cause an accident.

The differential locks must not be activated when the vehicle is being towed or while the wheels are spinning.

Only engage the differential locks manually if traction in automatic mode is insufficient.

The differential locks can be activated manually up to a speed of 19 mph (30 km/h).

► Start the engine.
► Turn selector wheel 1 to desired position 3 or 4.

The indicator lamp in selector wheel :

lights up at the corresponding symbol.

The engaged differential appears in the multifunction display:

5 The differential lock for the transfer case is locked.

If you have not previously selected the offroad menu in the on-board computer, the message disappears after about five seconds.

The differential locks are not controlled automatically. The steerability of the vehicle is restricted considerably. Drive carefully and accelerate gently for optimum traction.

If the differential locks are activated manually, the wheels scuff on the road when cornering since the rotation difference between the wheels is no longer balanced out.

You can switch back to automatic mode at any time. For safety reasons, the differential locks are deactivated automatically at speeds over 31 mph (50 km/h). If you stop the vehicle and switch off the ignition for longer than ten seconds, the differential locks switch back to automatic mode.

Message in the multifunction display

Diff. lock system overheated.

Wait briefly.

The differential lock system has overheated and briefly disengaged.

► Continue driving.

The differential locks cool off and are soon available once again.