The last Hyundai Sonata was a striking stylistic departure from usually bland mid-size sedan styling.

The new one, not quite so much: To our eyes, there's very little aside from the badges that identifies it as a Hyundai.

We spent a few days with a 2015 Hyundai Sonata Limited, a test car so new it didn't even have a window sticker, to see if it improved on the gas mileage of its predecessor.

[UPDATE: Hyundai later provided us with a complete window sticker for our test car; see end of article for the full rundown.]

DON'T MISS: 2015 Hyundai Sonata - full review

The new base model of 2015 Sonata gains 1 mpg combined on the superseded 2014 base car:

The heavier Limited model we drove was rated at 28 mpg combined (24 mpg city, 35 mpg highway), although the base version comes in at 29 mpg combined (25 mpg city, 37 mpg highway).

2015 Hyundai Sonata 2.4 Limited

2015 Hyundai Sonata 2.4 Limited

That compares to 2014 ratings for the base car that were 1 mpg lower in combined and city rankings, and 2 mpg lower for the highway cycle.

Our 2015 Sonata Limited was powered by a 185-horsepower 2.4-liter four-cylinder engine paired with a six-speed automatic that drives the front wheels.

Overall, we logged 30.4 mpg on a 362-mile test drive that broke down to about two-thirds highway miles and one-third city stop-and-go and suburban traffic.

That's better than the combined rating of 28 mpg, though not quite as high as we might have hoped for from the highway-heavy drive cycle.

For the very best gas mileage in the new 2015 Sonata lineup, however, there are two other choices as well.

The first is the 2015 Sonata Hybrid, which is a carryover model using last year's design; its ratings are unchanged at 38 mpg combined (36 mpg city, 40 mpg highway).

2015 Hyundai Sonata 2.4 Limited

2015 Hyundai Sonata 2.4 Limited

The other is a new 2015 Sonata Eco model that will follow the launch of the volume versions by a few months. It uses a smaller 1.6-liter engine and the same six-speed automatic, and is expected to earn ratings of about 32 mpg combined (28 mpg city, 38 mpg highway).

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We hope to test the Sonata Eco once it's on sale.

Smoother engine, substandard cruise

Hyundai says it's retuned the carryover 2.4-liter engine to make it more responsive at low and mid-range engine speeds.

That's largely true, and in gentle to medium driving, the new Sonata is smooth, quiet, and comfortable--more so than the previous model, which could get raucous.

The body structure has also been stiffened, and the car scores well on refinement in normal usage.

2015 Hyundai Sonata 2.4 Limited

2015 Hyundai Sonata 2.4 Limited

The one glaring exception to this is the Limited model's adaptive cruise control, which is one of the clumsier, coarser, and least pleasant such systems we've tested.

In comparison not only to various German luxury sedans, but even to the 2015 Subaru Outback we tested the previous week, the 2015 Sonata's adaptive cruise feels abrupt, slow to react, and jerky in both acceleration and braking.

Granted, the Subaru had a continuously variable transmission (CVT) that may have made power transitions smoother and more gradual.

Still, we were startled when a steady uphill grade at highway speeds caused the Sonata's cruise-control system to oscillate between two gears: 10 seconds in one, downshift to a lower gear for 10 seconds, upshift for another 10 seconds ....

2015 Hyundai Sonata Limited, test drive, Hudson Valley, NY, Aug 2014

2015 Hyundai Sonata Limited, test drive, Hudson Valley, NY, Aug 2014

Other thoughts

Other than the coarse cruise control, the new Sonata Limited proved itself a pleasant, innocuous, and comfortable mid-size sedan.

Behind the wheel, we were impressed by the weighting and feedback of the electric power steering, something that many automakers don't seem able to get right

Of the three drive modes--Normal, Eco, and Sport--we largely used Normal, as the Eco produced the usual frustrating slower response--tedious in traffic

There's also a manual gear-selection mode ("S") on the shift lever, though no steering-wheel paddles; in a car like this, do people ever actually shift for themselves?

2015 Hyundai Sonata Limited, test drive, Hudson Valley, NY, Aug 2014

2015 Hyundai Sonata Limited, test drive, Hudson Valley, NY, Aug 2014

A few further impressions of the new 2015 Sonata:

  • The cabin of the Limited model is elegant and restrained, with a handsome beige and black two-tone, although the high-quality soft-touch plastic surfaces aren't actually that soft
  • There's lots of useful storage inside the car, from door pockets and console cup-holders to a covered bin and a sliding-door compartment, plus a small tray--even with a conventional shift lever sprouting from the console as well
  • The rear seat offered decent room for adults, but both the lower cushion and the seat-back are quite reclined--and the seat is low to the floor as well
  • Rear three-quarter vision is decent for a modern car designed to meet the latest crash-safety standards, though the high tail makes the rear-vision camera all but mandatory for reversing
  • The memory settings for seat and mirror positions (though it didn't include steering wheel position, which is manually adjusted) comes with a set of instructions on the display between the instruments--very smart, and the first time we've seen this on a test car
  • The navigation system includes a speed-limit overlay that's one of our favorite new digital features in high-end luxury cars, and delightful in a mass-market car like this one

2015 Hyundai Sonata Limited, test drive, Hudson Valley, NY, Aug 2014

2015 Hyundai Sonata Limited, test drive, Hudson Valley, NY, Aug 2014

While less distinctive than its predecessor, the 2015 Hyundai Sonata is more refined and appears to be marginally more fuel-efficient--though we're really waiting for the Sonata Eco model with the smaller engine.

Meanwhile, we expect the mainstream versions to sell as well as the previous model that put Hyundai into serious contention in the mid-size sedan segment--and perhaps better.

UPDATE: Our 2015 Hyundai Sonata Limited test car carries a base price of $26,525, with a list of standard features far too lengthy to reiterate here.

A $3,500 Tech Package added the panoramic sunroof, a navigation system with an 8-inch touchscreen, xenon headlamps, the heated and ventilated front seats, memory function for the seat and mirror positions, and a high-end audio system with satellite and HD radio, among other features.

The $1,500 Ultimate Package on top of that added the adaptive cruise control, lane-departure warning, forward-collision warning, rear parking assistance, an electronic parking brake, and automatic high beams.

The only option was a $150 package of carpeted floor mats. Adding the mandatory $810 delivery fee, the bottom line on our test car came to $32,510.


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