Optimally tailored to the track: the semi-active COMFORT DRIVE chassis 

The ‘proactive’ semi-active chassis that provides active support: AL-KO COMFORT DRIVE ensures greater driving safety and comfort in your motorhome. It reacts independently to driving manoeuvres such as braking, accelerating or cornering, and compensates for bumpy roads by automatically adjusting the shock absorbers. The chassis can be installed ex works or retrofitted.

Depending on the road conditions, select the optimum mode for more driving comfort and directional stability: The basic “Normal” mode improves driving comfort and lane handling, and is ideal for winding roads where a lot of steering is required. The switchable “Comfort” mode is suitable for long, straight stretches such as motorways.

Advantages of the COMFORT DRIVE chassis for motorhomes at a glance

COMFORT DRIVE combines safety and driving comfort. Specifically:

• Compensation for uneven road surfaces: The semi-active chassis compensates for unevenness – within the physical limits. Grip and traction are optimised, especially on slippery surfaces.
• Reduced vibrations and acceleration jerks: The AL-KO COMFORT DRIVE can reduce motorhome vibrations and acceleration jerks by up to 20 percent.
• Increased vehicle stability and safety: The semi-active chassis reduces wobbling and tilting by reducing the motorhome’s rolling movements when cornering. This leads to better road holding and increases driving safety. The vehicle swings less and brakes more gently, shortening the braking distance.
• Support during emergency braking: if things get tight, the system supports you by changing the shock absorber functions – crucial in the event of emergency braking.
• Reduced driving noise: reducing the vibrations significantly reduces the noise level generated as well.
• Individual adjustment of the driving mode: the AL-KO COMFORT DRIVE offers the choice of two driving modes: Normal and Comfort. 
• Adaptation to the loading conditions: in motorhomes, the load condition has a major influence on the weight distribution. A semi-active chassis can adjust the damping accordingly to keep the driving response nicely balanced.

How exactly does the COMFORT DRIVE semi-active chassis work?

The semi-active chassis calculates the expected vehicle movement and changes the shock absorber settings based on this – automatically and almost in real time. This significantly reduces movement along the vehicle axle and noticeably absorbs shocks and impacts.

Seven sensors constantly monitor the vehicle's behaviour and pass this information on to the shock absorbers. These in turn continuously adapt their damping properties to the road conditions to ensure an optimum driving experience. In addition, the chassis reacts automatically to the load condition as well as to sudden side winds; it is also connected to the motorhome's electronic stability programme (ESP) via an interface.

What is the difference between the COMFORT DRIVE and an original chassis?

Standard chassis components are designed by the respective vehicle manufacturers for the widest possible range of applications, particularly in the areas of trade, mail delivery and transport. Loading takes centre stage here – where functionality and flexibility count.

The problem: A delivery van is used to transport very different loads, usually over short distances with stops in between. In comparison, a motorhome is a true endurance athlete: (almost) always fully loaded, it covers several hundred to a thousand miles every trip – at a relatively constant driving speed and with only a few short breaks along the way. Motorhome travel needs to be comfortable, quiet and relaxed. AL-KO COMFORT DRIVE is specially tailored to these requirements.

What is the difference to an active chassis?

The difference between an active and a semi-active chassis lies in the way it detects the road surface and the driving situation and how it adapts and controls suspension characteristics accordingly.

Active chassis recognise uneven road surfaces and driving situations even before the vehicle has to navigate them and change the settings proactively. These systems access various in-vehicle systems and their information such as camera, radar and lidar. They communicate with each other via the vehicle's own electronic interfaces.

Semi-active chassis work by recording the movements and accelerations of the chassis and body components. The chassis is continuously monitored by the integrated system sensors. The suspension components’ functions are adjusted within an electronic map.

Where is the COMFORT DRIVE installed?

The COMFORT DRIVE is installed on the chassis, on the shock absorbers, to be precise. The sensors for measuring the vehicle movements are attached to the vehicle body and the wheel mounts. In addition, the vehicle is fitted with springs and dampers on the front and rear axles as well as a control unit under the driver's seat. The semi-active suspension system integrates with the existing suspension and works with the shock absorbers to adjust the damping settings.

The AL-KO COMFORT DRIVE replaces all shock absorbers (left and right on the rear axle/rear wheels and on the front suspension struts) with controlled shock absorbers. In addition, sensors are fitted to all wheels and the chassis too. A corresponding control unit for communication between the controlled shock absorbers and the sensors is located in the driver’s seat box. A button on the dashboard can be used to switch the system from permanently active Normal mode to Comfort mode, e.g. for longer motorway journeys.

Which motorhomes is the AL-KO COMFORT DRIVE suitable for?

AL-KO currently offers the semi-active chassis for motorhomes based on the Mercedes-Benz Sprinter in conjunction with the AL-KO AMC chassis.

The PSM module or its pre-fitting by Mercedes-Benz is absolutely essential for this. Installation can be carried out by any AL-KO customer centre or a certified wholesaler.