The E 220 d 4Matic All Terrain prototype we’ve been invited to ride in is close to 100% representative of the definitive production version, reveals Schneider. “Mechanically, it’s identical to the showroom car. The tuning of the engine, gearbox, chassis and electrics is production specification. There’s some fine tuning to be done to body quality, and there are some fit and finish issues, but it’s very close to what you can expect when deliveries begin,” he says.
Power for the new model hails from Mercedes-Benz's new turbocharged 2.0-litre four-cylinder diesel. This OM654 unit provides the E 220 d 4Matic All Terrain with 191bhp and 295lb ft of torque on a relatively narrow band of revs between 1600 and 2800rpm. Drive is channelled through a standard nine-speed torque converter-equipped automatic gearbox and a specially tuned version Mercedes-Benz’s 4Matic four-wheel drive system.
Our route around a former army training ground about an hour’s drive south of Stuttgart, Germany, takes in a variety of different road surfaces, including loose chip, gravel, the obligatory sludge and a couple of moderately deep water crossings.
The new E-Class All Terrain takes it all in its stride, traversing them with surprising authority for a car eningeered primarily for road use. Given the fact the prototype is running the standard road-biased tyres, not the optional snow and mud suited rubber, it's a particularly impressive performance that fully underlines the car's ability on the rough stuff.
With the four-wheel drive system doling out power to either the front or rear depending on prevailing grip, the E-Class All Terrain makes light work of the variety of different roads. Traction remains strong despite challenging conditions, allowing us to retain good momentum even when we’re faced with steep inclines, muddy holes and, at one point, an creaky old bridge once used for military rescue training.
With limited ground clearance and an obvious lack of scratch production along its flanks, however, the E-Class All Terrain is never going to forge its own progress across uncharted territory in the way a tougher and truly dedicated off-roader like its stablemate, the iconic military-grade G-Class, might.
An optional digital display within the E-Class All Terrain's vehicle settings menu provides information on the angle of attack, which at one point reaches more than 50deg on a particularly slippery incline of wet, hard-packed gravel. As if to highlight the traction generated by the new car’s four-wheel drive system, Schneider stops before the summit and then, relying on the strong torque characteristics of the diesel engine, slowly creeps forward in first gear. There’s some whirring sounds from underneath but little slippage before traction is regained and we surmount the crest of the hill.