Mercedes-Benz G-Class to get kinetic suspension

Mercedes-Benz has announced plans to update the G-Class four-wheel-drive about the same time as the electric Vision EQG joins the line-up next year.

The revised Mercedes-Benz G-Class, pictured above testing in prototype form ahead of a planned unveiling in mid-2024 – in images supplied by the German automaker – is poised to receive a number of improvements, including a new semi-active suspension similar to that already adopted on the German car maker’s latest SL and GT sports cars.

To be offered as an option on the G63 4Matic, the so-called kinetic suspension does away with traditional anti-roll bars. They are replaced by an advanced damping system featuring interconnected electro-hydraulic flow valves that constantly vary the rebound and compression properties.

The new kinetic suspension alters damping force from side to side and from front to rear depending on a series of factors, including speed, steering wheel angle, body movement, driving mode, and road conditions.

The compression units of the dampers on one side of the new G63 are linked via the electro-hydraulic flow valves to the rebound units of the dampers on the other side, and vice versa.

When a wheel compresses, the piston within the damper extends upwards, and hydraulic fluid flows across to the other side to support the rebound properties of the opposite damper.

The action results in an improvement in body control, ride quality, and off-road performance, according to Mercedes-Benz, which is also developing the kinetic suspension for other upcoming production models.  

The stiffness of the dampers is controlled by two so-called accumulators – one for the front and another for the rear wheels, in the form of a metal-shaped sphere filled with nitrogen gas. It uses a flexible membrane to collect excess hydraulic fluid and distribute it under pressure into the electro-hydraulic flow valves for added roll stiffness when required.

Because the compression and rebound properties act independently, the kinetic suspension is claimed to provide a wider tuning range between minimum and maximum damping levels. It is also able to provide resistance to pitch and dive. Wheel articulation is also said to have been improved.

By replacing the roll bars, the new system also provides an as yet unspecified saving in weight.

The kinetic suspension was originally developed by Australian inventor Chris Heyring and industrialized by US company Tenneco under the Monroe brand. It was used successfully by Citroën in the World Rally Championship during the early 2000s before being banned by the world’s motorsport governing body, the FIA.  Other car makers to use the system on production vehicles include McLaren and Rivian.  

Further changes in store for the G63 in 2024 include the adoption of a new mild-hybrid drivetrain. Already used by the GLE63 S 4Matic, it combines AMG’s twin-turbocharged 4.0-litre petrol engine with a 48-volt starter generator. The former develops 450kW and 850Nm with the latter offering up to 16KW and 250Nm. This compares to the 430kW and 850Nm of today’s G63.

“A significant leap in suspension development.” That’s how Ralf Haug, head of suspension development at Mercedes-AMG, describes the G-Class’s new kinetic suspension as we scythe down a narrow and bumpy country road outside of Leipzig in Germany during the development of next year’s G63.

“It gives us greater breadth of ability between the various driving modes. We’re able to go softer at one end and firmer at the other end of the spectrum, than we are with the more conventional suspension and the anti-roll bars that we use today. It also offers faster and more fluid response with greater body control and the foundation for than we have now,” he adds.

The idea for the adoption of the kinetic suspension on the G-Class came after Mercedes-AMG started development of the advanced system for the eighth-generation SL and its sister model, the second-generation GT, says Haug.

“We saw the advantages it brought to our sports cars and immediately began thinking what it could do for our off-road models,” he reveals.

It’s still early days, but if the prototypes we rode in are any indication development is already well advanced. It is never easy judging a car from the passenger seat, but next year’s G63 appears to offer improved handling qualities and a calmer ride than today’s model.

The big surprise, however, is just how well the new suspension suppresses body roll. With the advanced dampers controlling the roll stiffness, there’s very progressive lean and, given the amount of suspension travel, limited body movement, even in tighter corners. The ride also appears to have gained added suppleness in all driving modes.

There’s clearly an improvement in on-road dynamics and, as Mercedes-AMG points out, a greater spread in driving characteristics.

Another advantage of the kinetic system, says Haug, is improved traction. This is displayed to great effect on an off-road course, where the new G63 tackles tricky inclines and storms along sandy tracks with great authority and a level of sure-footedness few if any rivals are likely to match.

While the G-Class’s off-road ability has never been in doubt, it appears the advanced underpinnings provide it with a further degree of ability away from the bitumen.