2018 Mercedes-Benz E-class Diesels

The list of Dieselgate victims is not limited to those who believed the hype and availed themselves of those dirty, cheating Volkswagens, Audis, and Porsches. The scandal also sent tremors through the wider industry. While some automakers have chosen to weather the storm and keep selling diesels in the United States—Jaguar Land Rover has launched its new-generation Ingenium diesel engines, and Chevrolet sells the Cruze and Equinox diesels—others have hit pause. And there’s the strong sense that, at many automakers, the corporate finger is hanging over the stop button.

That’s certainly the case with Mercedes-Benz and its E-class. Despite being one of the pioneers of diesel passenger cars in the States—with an impressive percentage of its seemingly unkillable 300Ds still chugging along four decades later—Mercedes has cold feet. The brand put a moratorium on U.S. sales of new diesels in May, and we don’t sense any sign of it reversing that position.

Happy Union

The E-class fundamentals are the same on both sides of the Atlantic—German dentists appreciate the same sense of quality as Floridian ones do. The European iteration of the current W213-generation car shares the same understated good looks, immaculately crafted cabin, and sense of dynamic stability. But the union with the big turbocharged 3.0-liter diesel V-6 that powers the range-topping E350d is a particularly happy one.

Part of the long-serving OM642 engine family, this V-6 is a direct descendant of the engine that did duty in the previous-generation E350 Bluetec sold here. Displacement is unchanged at 2987 cc, but output has risen by 44 horsepower to 254 and is accompanied by 457 lb-ft of torque, which is available from just 1600 rpm. The car we drove was rear-wheel drive, although all-wheel drive also is available. Both versions use the same nine-speed automatic transmission shared with the entire E-class range.

The engine statistics perfectly reflect this powerplant’s low-down urge and relaxed progress. The diesel pulls strongly from its modest torque peak and upward, and the gearbox shifts intelligently to keep revs down. A gentle accelerator application will deliver forceful quickening; the E350d pulls away from traffic even if you restrict yourself to the top inch of the pedal’s travel. But pushing harder delivers more, with the transmission switching out of its miser mode, where it upshifts as quickly as possible, to a more aggressive map that keeps the engine in its deep-chested midrange. What it doesn’t do is rev. According to Mercedes, peak power arrives at a modest 3400 rpm, and even under the hardest use the E350d’s engine won’t spin beyond 4000 rpm, a long way short of the 5250-rpm redline that is marked in pixels on the digital instrument cluster.

This is not the most civilized of diesel powerplants, but only in comparison with the increasing excellence of some of the competition. The E350d is far from the sort of loutish anvil chorus that used to mark compression ignition, without any clattering or harsh harmonics and with only the slightest vibration through the steering wheel at idle. But it is a measure louder than the freakishly quiet BMW 530d when pushed. Nor can it match the urge of diesel-powered leviathans such as the Audi SQ7 and Bentley Bentayga SUVs (that are mechanically related to each other). Performance feels brisk rather than rapid, despite the E350d’s ability to hit the same 155-mph limiter that Mercedes fits to most of its quicker European offerings. Attempting to match the automaker’s claim of a 5.9-second zero-to-62-mph time would miss the car’s laid-back mission.

In the interest of sampling the full platter of forbidden fruit, we also had a turn in the four-cylinder E220d, which uses Mercedes’ OM654 engine, a new architecture developed at huge cost. The E220d falls some way short of the E350d in terms of both power and performance, with 192 horsepower and 295 lb-ft of torque. The E220d lacks the E350d’s effortless muscularity and needs considerably more accelerator pressure to deliver a similar level of perceived acceleration. Yet it’s no slouch: Benz’s claim of a 7.3-second zero-to-62-mph time is pretty much identical to the time we extracted from the old six-cylinder E350 Bluetec.

Downsizing brings other benefits, though. While still no track-and-field star, the E220d feels more agile and responsive when asked to change direction, thanks to reduced weight over the front wheels; Mercedes figures the car is about 260 pounds lighter than the six-cylinder. The new engine is quieter than the V-6 as well, and it is capable of delivering some seriously impressive fuel economy. The official European combined figure of 72 mpg is as fanciful as these things tend to be, but in real-world use owners are reporting better than 45 mpg.

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