When it introduced the current-generation F-150 half-ton pickup truck for the 2015 model year, one of the major points Ford touted was fuel economy.

It claimed the light-duty F-150's aluminum body saved over 700 pounds compared to previous steel body, helping to improve efficiency.

When it came time to redesign the Super Duty line of heavy-duty trucks, Ford also decided to use a similar aluminum body.

DON'T MISS: Just how 'green' is a Ford Super Duty truck?

But rather than using aluminum to lower overall vehicle weight, as in the F-150, Ford mostly used it to compensate for weight increases in the Super Duty's steel frame and other places.

In this case, fuel economy took a backseat to towing capacity and other considerations.

That's not surprising, because while automakers are paying more attention to the efficiency of half-ton trucks, they still don't have to report the fuel economy of heavy-duty pickups.

2017 Chevrolet Silverado 2500HD

2017 Chevrolet Silverado 2500HD

So while fuel economy may be a good reason to buy a Ford Super Duty over, say, a Chevy Silverado HD—or vice versa—you'll never know which one has higher ratings.

That may have made sense when the current rules were drafted decades ago, but now it may be time for manufacturers to start reporting heavy-duty truck fuel economy, argues Jalopnik (in somewhat saltier language than we might use).

Models like the Ford F-250, F-350, and F-450, Chevrolet Silverado 2500 HD and 3500 HD, Ram 2500 and 3500, and Nissan Titan XD all fall under a different classification than more conventional light-duty pickup trucks.

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The smaller trucks are regulated in the same way as passenger cars and SUVs: their makers must submit fuel-economy information to the Environmental Protection Agency, and post that information on window stickers.

But that rule does not apply to trucks with a Gross Vehicle Weight Rating (GVWR) of 8,500 pounds—defined as the total maximum weight of the truck and its cargo.

When these standards were first drafted, decades ago, it was inconceivable that individual consumers would buy such large vehicles for any kind of personal use.

2017 Ram 2500 Off-Road

2017 Ram 2500 Off-Road

The heavier-duty pickup trucks then were robust but basic machines for tradesmen and specific work applications that required their capabilities, including tasks like road repair and electric-utility maintenance.

Times change, though.

At the press launch for the 2017 Super Duty in Colorado, Ford was quick to note the truck's popularity among commercial buyers, and said the new model was designed with those buyers in mind.

MORE: Pickup Truck Fuel Economy For 2016: Diesels Take Top Three Spots (Nov 2015)

But a Ford representative also described the Super Duty as a "luxury car with a pickup box."

Indeed, the Super Duty can be ordered with many features one would expect to find on a luxury car, including massaging leather seats and a panoramic glass roof.

It's part of a trend toward more upscale trucks, as manufacturers try to cater to buyers that view them as more than just work vehicles.

2016 Nissan Titan

2016 Nissan Titan

Even if heavy-duty trucks were bought purely for vocational use, of course, reporting fuel economy would still benefit their buyers.

While Ford claims those buyers care more about towing and cargo capacity than fuel economy, it's hard to imagine at least some buyers not being tempted by the money to be saved from using less fuel.

Until the EPA requires carmakers to report fuel-economy figures like they do for their other models, though, consumers won't be able to make a comparison.

2016 Ford Super Duty F-250 SRW 2WD SuperCab 142

2016 Ford Super Duty F-250 SRW 2WD SuperCab 142

The second phase of the current administration's ambitious plan to reduce greenhouse gases, however, will include specific provisions dealing with commercial, vocational, and increasingly popular heavy-duty trucks.

While it’s unclear what rules may change when those proposed regulations take effect in 2021, it’s likely that heavy-duty trucks will, for the first time, need to comply with some sort of emissions-reduction plan.

Environmental officials have already said that any advanced technology added to the trucks for that purpose would pay the owners back in fuel savings within a few years.

While pickups account for just 15 percent of the overall emissions produced by the heavy-duty segment (semi-tractor trailers are a whopping 66 percent) analysts have said that they could become a much larger proportion of the total if their sales continue to grow at the current rate.

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