Building on the foundation of its original, well-proven 4MATIC permanent all-wheel-drive system Mercedes-Benz has announced details of a new generation of this vehicle-dynamics technology developed specifically for cars based on front-drive architecture and fitted with transversely mounted engines. The first model in the automaker’s lineup to offer this new-gen 4MATIC system is the 2014 Mercedes-Benz CLA-Class, a stylish compact entry-level sedan that will make its debut at the Geneva Auto Show next March and go on sale here later in the year. This new system will be offered on the car’s high-performance sibling, the CLA45 AMG that also will be introduced at some point in 2013.
Key elements that differentiate the new 4MATIC package from the existing M-B setup include a new power take-off to the rear axle which is integrated in the car’s 7G-DCT automated dual-clutch transmission and a rear-axle gear unit that incorporates an electro-hydraulically controlled multi-disc clutch. In addition to being lighter — up to 25 percent compared to competitor’s AWD setups — the new 4MATIC system permits full, precise and near-instantaneous variable distribution of drive torque from the CLA250’s 2.0-liter 4-cylinder engine between the front and rear axles.
Operating under the algorithm "as often as necessary, as rarely as possible," the new torque-on-demand 4MATIC system keeps the multidisc clutch in "open" mode until it senses slippage, letting the CLA function in its most fuel-efficient manner as a pure front-driver. However, when surface conditions do dictate, the system can engage in a matter of milliseconds and send up to 90 percent of the drive torque to the rear wheels.
Fully integrated into the CLA’s standard ESP (Electronic Stability Program) and 4ETS (Electronic Traction System) that also permits selective braking of individual wheels, M-B’s new 4MATIC for front-drive includes an ECO mode that allows the driver to toggle program mapping between ECO, Normal and Sport settings. In AMG spec, the system features an even more aggressive 4MATIC implementation that applies additional rear-biased torque in conjunction with the 3-stage AMG-spec ESP program (ESP On/ESP Sport Handling/ESP Off) to permit more spirited cornering.
