General Motors' pair of small crossover utility vehicles has both managed to achieve impressive new safety ratings.

The mechanically-identical 2015 Chevrolet Trax and 2015 Buick Encore received a "Top Safety Pick" label from the Insurance Institute for Highway Safety (IIHS).

DON'T MISS: 2015 Chevrolet Trax: First Drive

This marks an improvement for the Encore, which has been on sale in the U.S. since the 2013 model year, and helps the newly-introduced Trax get off to a strong start.

The Buick previously fell short of the Top Safety Pick rating because it received a "Poor" rating in the new and challenging IIHS small-overlap frontal crash test.

2015 Chevrolet Trax

2015 Chevrolet Trax

The test is meant to replicate a collision with the corner of another vehicle, or a fixed object with minimal surface area such as a tree or pole.

Structural improvements incorporated into the shared chassis allowed the 2015 Encore and Trax to achieve a top "Good" rating for the small-overlap test. They received that score in all four other categories as well.

The Top Safety Pick rating is surpassed only by Top Safety Pick +, which was added recently to recognize automatic-braking systems that can slow a car without any driver intervention.

MORE: 2013 Buick Encore: Subcompact Luxury Crossover, Drive Report

One of these systems is available on the Encore, and received a "Basic" rating from the IIHS. Automatic braking is not available on the Trax.

Both vehicles also received 5-Star Overall Vehicle Scores from the National Highway Traffic Safety Administration (NHTSA).

They earned five-star ratings in the frontal and side crash-test categories as well, and four stars for the rollover test.

2015 Buick Encore

2015 Buick Encore

Aside from their styling, bodies, interiors, and equipment, the Encore and Trax share virtually identical platforms and running gear, components also used for the Chevy Sonic subcompact hatchback and sedan.

They also share a single powertrain, consisting of a 1.4-liter turbocharged four-cylinder engine and six-speed automatic transmission, with standard front-wheel drive or optional all-wheel drive.

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The Chevy has a slight fuel economy advantage over the Buick, though.

It gets an EPA-rated 29 mpg combined (26 mpg city, 34 mpg highway) with front-wheel drive and 27 mpg combined (24 mpg city, 31 mpg highway) with all-wheel drive.

The Encore, with more standard features adding to its weight, loses 1 mpg in each category with either front- or all-wheel drive.


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