The road-simulation test rigs are just as punishing as the body testing facility. Applying identical load spectra over the same distance, the test engineers torture the M-Class chassis in all of its different variants here - from the basic steel suspension with selective damping to the AIRMATIC ADS air suspension to the version with the new ACTIVE CURVE SYSTEM. In contrast to the body testing facility, only the chassis is installed on the test rig here. The pivot points are fixed to the solid test rig frame, while the wheel hubs are connected to the servo-hydraulic cylinders using special mounting fixtures. This test setup allows the complete chassis to be examined in isolation, producing even more exact findings.

Compared to the testing for road-going saloons, the programme for a Mercedes-Benz SUV is far more rigorous. As with the body testing facility, the chassis is also subjected to all manner of different on-road and off-road load cycles. In contrast to real-life driving with prototypes, which continues to take place too, the constant laboratory conditions on the road-simulation test rig allow the engineers to analyse individual chassis parameters more effectively, and thereby take targeted action to correct any vulnerabilities found during development. The several weeks of laboratory testing staged over a distance of 3000 kilometres would take about half a year if carried out under real-life conditions.