Are you driving a car or a truck? The answer may be harder to determine than you think.

U.S. safety and emissions regulations generally split cars and trucks into two categories, but the line between those two vehicle types has become blurred in recent years.

That's thanks to the car-based crossover utility vehicle, which now represents one of the most popular vehicle segments in the U.S.

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Crossovers have SUV-like bodies, but use car-like unibody platforms, rather the body-on-frame designs that placed traditional SUVs firmly in the truck category.

The distinction between car and truck likely doesn't matter much to consumers shopping for new SUVs, but it is consequential in terms of regulations, argues a recent Navigant Research blog post.

That's because manufacturers can use ambiguities in the current regulations to lessen the difficulty in meeting Corporate Average Fuel Economy (CAFE) standards, while still selling lots of popular SUVs.

2016 Toyota 4Runner

2016 Toyota 4Runner

Current CAFE standards require automakers to achieve a fleet average of 54.5 mpg (equivalent to about 40 mpg in the real world) by 2025, and include different classification procedures for cars and trucks.

Cars are classified based on combined passenger and cargo volume, while trucks are classified by gross vehicle weight rating (GVWR).

Efficiency targets are slightly less aggressive for trucks, which must average a 3-percent improvement each year from 2012 to 2025, compared to 5 percent for cars.

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However, the Environmental Protection Agency (EPA), which oversees compliance, has no specific definition for crossovers, so manufacturers essentially get to choose segments to fit them into.

These segments include "small," "mid-size," or "large" car, and "small" or "standard" SUV.

But the small SUV category is also split into "two-wheel drive" and "four-wheel drive" subcategories, with "two-wheel drive" models considered cars, and "four-wheel drive" models considered SUVs.

2017 Nissan Pathfinder

2017 Nissan Pathfinder

That means a model with multiple drivetrain options could be classified as both a car and a truck.

That's the case with the Nissan Pathfinder which, with a GVWR of 5,985 pounds, comes in just under the 6,000-pound maximum weight for "small" SUVs.

So front-wheel drive versions of the Pathfinder are considered cars, while all-wheel drive versions are considered trucks, as far as the EPA is concerned.

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Meanwhile, the Nissan Murano crossover is actually classified as a mid-size station wagon.

These somewhat unusual classifications allow automakers to balance their fleet averages for cars and trucks, according to Navigant.

Consumers won't pay much attention to these arbitrary categories, but the practice does allow manufacturers to continue to meet emissions standards without directly improving efficiency.

2017 Nissan Murano

2017 Nissan Murano

It also echoes the Detroit automakers' original push for SUVs in the 1990s and early 2000s.

As described by Keith Bradsher in his book High and Mighty: The Dangerous Rise of the SUV, automakers gravitated to vehicles that could be classified as "light trucks" because the safety and emissions standards for that category for less strict.

But now that SUVs are beginning to overtook sales of conventional cars, a shift toward more utility vehicles for the sake of regulatory expediency could be more consequential.


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