We've finally had a chance to test out the fuel economy of the new and very popular smallest Mercedes-Benz, the 2014 CLA 250 sedan.

The company has been struggling to meet global demand for the car, which is both the smallest Mercedes in many years and one of the least expensive.

We wanted to see whether it met its fuel-efficiency ratings, and we found that it did--at least in mostly highway use.

30-mpg base model

There are three models of CLA on sale this year, with the most economical model coming in at 30 mpg combined (26 mpg city, 38 mpg highway).

DON'T MISS: 2014 Mercedes-Benz CLA Class - Review

That's the front-wheel-drive version with a 208-horsepower 2.0-liter direct-injected and turbocharged four-cylinder engine, mated to a seven-speed dual-clutch automated manual transmission.

If you opt for 4Matic all-wheel drive with the same powertrain, EPA ratings fall to 27 mpg combined (24 mpg city, 32 mpg highway).

2014 Mercedes-Benz CLA Class

2014 Mercedes-Benz CLA Class

Finally, there's the hot-rod AMG version, known as the CLA 45 AMG 4Matic. It uses an uprated engine that produces a stunning 355 hp, has all-wheel drive standard, and comes in at 26 mpg combined (23 mpg city, 31 mpg highway).

The AMG, we have to admit, is huge fun to drive and beautifully neutral through hard cornering. It's pricey for its size, however, and has a certain amount of external flash and bling that we could live without.

Not a diesel, but...

Back to our conventional CLA 250, though.

ALSO SEE: 2014 Mercedes-Benz E 250 BlueTec Diesel: Fuel-Economy Review

It's not actually the most fuel-efficient model Mercedes offers. That would be the diesel E-Class mid-size sedan, known as the E 250 BlueTEC, which is rated at 33 mpg combined (28 mpg city, 42 mpg highway).

2014 Mercedes-Benz CLA Class

2014 Mercedes-Benz CLA Class

But on a five-day road trip that covered 617 miles through much of western Oregon, our CLA 250 compact sedan logged 34.5 mpg--per the car's digital information display.

That's better than the 30-mpg combined figure, but it should be. Our trip was at least two-thirds highway travel up and down the I-5 Interstate that connects Portland in the north to Eugene and then Medford and Ashland in the south.

Eco mode: entirely tolerable

We also left the CLA in its default "Eco" mode, the only way the start-stop system turns on.

Surprisingly, the CLA's "Eco" setting is one of the very few in any vehicle that we found tolerable for regular use. Most "Eco" modes are painfully slow and plodding, with some of the Toyota and Honda settings among the worst to endure.

Somehow, Mercedes has made an Eco mode that drives more or less like a normal vehicle. So much so, in fact, that it took half a day before it registered that the button on the console was lit--and that it could be turned off.

Well done, Mercedes-Benz.

Functionally, a two-seater

Overall, we found the CLA a pleasant car to travel long distances in. As a solo driver, anyhow.

MORE: 2014 Mercedes-Benz CLA: Detroit Auto Show Preview

The car has so little rear-seat room, between its short wheelbase and the sleek dropping roofline, that it might as well be a two-seater. We get the sense there's more usable cabin volume in a Nissan Versa subcompact sedan than this luxury "compact" sedan.

2014 Mercedes-Benz CLA 250, test drive in Oregon, July 2014

2014 Mercedes-Benz CLA 250, test drive in Oregon, July 2014

The lines are striking, don't get us wrong. Especially from the rear, the CLA deliberately evokes the "four-door coupe" shape of the much larger CLS. And that removes any risk of it being viewed as a small, nerdy front-wheel-drive economy sedan that happens to have a three-pointed star on the front.

The trunk is capacious, however, extending deep into the cabin under the raked rear window.

Luxury, with yellow stripes

Other random notes from our five days with the CLA:

  • The bright yellow stripe down the seats, echoed on the floor mats, was a delightful surprise that made us laugh; the Edition 1 package is an extra-cost option, of course
  • The matching yellow stitching on the dash top, however, reflected in the steeply raked windshield under almost any light condition
  • Inside, anyone who's driven a Mercedes-Benz will recognize the visual cues--big round vents, gauge faces, a column-mounted shift lever, and a cruise-control stalk on the left below the indicator--even if they're at seven-eights scale
  • A lot of details underscore the luxury positioning of the CLA, including the motors that power the frameless window glasses up or down when doors are opened or closed
  • The front seats felt like an odd blend: the backrests are heavily bolstered, comfortable, and very supportive, but the lower cushion is narrow and short, almost as if it were from a smaller car
  • Because the infotainment system didn't recognize our two-year-old smartphone, it wouldn't charge the device via the USB cable--it cycled power off and on every 5 seconds

2014 Mercedes-Benz CLA250 with Sport Package Plus

2014 Mercedes-Benz CLA250 with Sport Package Plus

Ferocious tire roar

Finally, the only major gripe we had with the CLA 250 was that on some of Oregon's coarsest highway surfaces (and it seems to have a LOT), the roar from the low-profile tires was so loud that it actually interfered with conversation and music.

The wheel-and-tire package was one of the many, many options that took this "$30,000 Mercedes" to a bottom-line sticker price more than 50 percent higher.

Starting at $29,900, our car added the "Edition 1" option package for a whopping $10,280.

That included a couple of dozen separate items, among them satellite radio and a Harman/Kardon surround-sound audio system, dual-zone climate control, heated seats, 18-inch AMG black-gloss alloy wheels with performance tires, sunroof, rear-vision camera, and a whole lot more--as well as the cool upholstery.

On top of that came a $2,500 Driver Assistance Package, with adaptive cruise control, blind-spot assist, and lane-keeping assist. The Parktronic and advanced parking assist feature was another $970, and the Cosmos Black paint added $720.

Pricey compact luxury sedan

With a mandatory delivery fee of $925, the bottom line was a very un-$30K-like $45,295.

Our conclusion: The new 2014 Mercedes-Benz CLA 250 is a largely comfortable small sedan that delivers on its fuel-mileage rating, at least for two people.

If you need to seat four regularly, however, you may be better off with the Mercedes E 250 BlueTEC mid-size sedan--which can run over $60,000 fully optioned.

Hey, no one said driving a German luxury car would be cheap.


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