The onslaught of four-cylinder engines into vehicles that previously wouldn't have had anything lower than six cylinders continues.

It's in the service of gas mileage, and the 2012 Mercedes-Benz C 250--with a 1.8-liter turbocharged and direct-injected four putting out 201 horsepower and 229 pound-feet of torque--is rated at 21 mpg city, 31 mpg highway, giving it a combined rating of 25 mpg.

That's a useful boost over the 228-hp 3.0-liter V-6 in last year's base C-Class model, the C 300, which was rated at 18 mpg city, 26 mpg highway, and 21 mpg combined.

Mercedes-Benz expects 40 to 45 percent of its C-Class buyers to opt for the four.

Over 220 miles, how many mpg?

So what kind of real-world mileage did we get in the new four-cylinder C-Class, the highest volume U.S. model for Mercedes-Benz?

On a five-hour trip covering 220 miles, including a climb most of the way up New Hampshire's Mount Washington (elevation 6,288 feet), the digital display on our C 250 coupe showed 27.7 mpg at an average speed of 43 mph.

The one caveat we should note is that almost the entire trip was on secondary and two-lane roads; there was no opportunity to hammer the 2012 C-Class down freeways at  prevailing 70-mph-plus speeds. Your mileage may vary.

Mercedes-Benz is hardly the only maker that's relying on higher-efficiency fours to replace base-level V-6 engines. Others include BMW, Hyundai, and various General Motors brands.

Mid-cycle refresh

For 2012, Mercedes-Benz has substantially revised the C-Class as it nears the midpoint of its life cycle. But you'd never know it on the outside, despite the 2.000-plus parts the company says it redesigned, with the changes largely confined to mechanical parts and a brand-new interior.

2012 Mercedes-Benz C-Class

2012 Mercedes-Benz C-Class

The exception is a new body style for the C-Class, a genuine two-door coupe that lines up neatly against the coupe version of the BMW 3-Series--against which the C-Class is often compared.

Mercedes-Benz executives referred routinely to the new style as a "true coupe," a "real coupe," and a "genuine coupe," underscoring the need for a two-door vehicle with a trunk--rather than a hatchback--in the U.S. market.

Handsome, light, and cramped

We think the coupe is handsome, if less distinctive than the larger and very aerodynamic E-Class coupe introduced a couple of years ago. But the carmaker says coupes will likely make up less than 10 percent of all C-Classes sold.

The C-Class coupe is definitely smaller in the rear seat than the sedan. A 6-foot person's head touches the headliner--meaning it bumps, not grazes--although the legroom is adequate if front-seat passengers are willing to move up a couple of notches.

Mercedes-Benz gets points for making the rear compartment lighter than most, by fitting a full-length panoramic sunroof as standard on the coupe. With the sun screen rolled back, rear-seat passengers don't feel confined to a dark cave as they do in the rear of so many other coupes.

2012 Mercedes-Benz C 250, Maine, September 2011

2012 Mercedes-Benz C 250, Maine, September 2011

Many gears, turbo lag

We drove both the C 250 with the four and the updated C 350, fitted with a 3.5-liter V-6 engine producing 302 hp. That engine in the four-door sedan is rated at 20 mpg city, 29 mpg highway, for a combined average of 23 mpg, though each figure loses 1 mpg in the C 350 Coupe.

Both engines are mated to the Mercedes-Benz seven-speed automatic transmission. For the first time, the C-Class no longer comes with a manual transmission on any model.

Having that many gears allows a transmission to be tuned to keep the engine turning at very low speeds, cutting fuel consumption. But the tradeoff is that to get acceleration on demand, the automatic has to kick down--and we found it often had to downshift two gears, not just one.

That issue applied to both engines, but we found it exacerbated in the C 250 by noticeable turbo lag. Altogether, it could take 2 or 3 seconds for the turbo to spool up enough to bring on the power for passing, while the transmission simultaneously downshifted from, say, 7th to 5th gear.

Our savior: paddles

It took us awhile to get used to this, but there's a simple solution. All C-Class models for 2012 are fitted with paddle shifters behind the steering wheel. A simple double tap on the left paddle brought up the revs, and positioned the car for those quick passes on two-lane rural roads.

2012 Mercedes-Benz C 250, Maine, September 2011

2012 Mercedes-Benz C 250, Maine, September 2011

Do Mercedes-Benz buyers often shift their own gears, let alone using paddles behind the wheels? We're not sure about that, but we suspect that C 250 owners will want to learn fairly quickly.

The company claims a 0-to-60-mph time of 7.1 seconds in the C 250, the same figure as for last year's older, thirstier 3.0-liter base V-6, as well as slightly more torque (229 lb-ft versus 221).

One final coupe note: Next March, a C 350 coupe with 4Matic all-wheel drive will join the lineup, although the comparable C 300 4Matic all-wheel drive sedan will stick with the old 3.0-liter engine, the only model in the whole range to do so.

Upgraded interior

Unusually for a mid-cycle refresh, the new C-Class interior includes an entirely redesigned dashboard. The soft-touch plastics are an improvement over the previous generation's hard surfaces, and a larger 5.8-inch display is mounted high up where it's easiest for the driver to see.

In terms of styling, Mercedes seems almost to have taken a leaf out of the Audi book, with its simple geometric black surfaces highlighted by a restrained piece of angled matte silver trim.

Despite the profusion of identical, rectangular black buttons (we counted roughly two dozen), the controls are fairly easy to use, and the type and graphics on the new display are definitely a step up.

2012 Mercedes-Benz C-Class

2012 Mercedes-Benz C-Class

The 60-40 split folding rear seat back makes the coupe usefully practical.

The rear seat is not only tight, however, but made up of two bucket seats with a hard-plastic cupholder insert between them. You'll only really want to put children or small adults back there anyhow.

From $36K upward

The 2012 Mercedes-Benz C 250 sedan carries a base price of $35,675 (including a mandatory $875 delivery fee), with the coupe starting at $38,095. With a group of 13 new features added for 2012, the company calls this a 4.1-percent increase in value over last year's mix of features, prices, and options.

Our test coupe (in bright Mars Red) carried a total sticker price of $43,790, which included a Premium I options package ($1,995), the Advanced Agility suspension upgrade ($1,400), the COMAND "single-disk" navigation package ($930), the mBrace telematics system ($660), a rear-view camera ($460)--and a $250 charge for something called "SPC special order" that we forgot to ask about.

The 2012 C-Class sedans have already arrived at Mercedes-Benz dealers, and coupes will have joined them by the end of this month.

Mercedes-Benz provided airfare, lodging, meals, and a lot of entertainment--planned and unplanned--to allow High Gear Media to bring you this first-hand drive report.


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