The new 2019 Chevrolet Silverado and Ram 1500 pickups will reduce gasoline consumption and greenhouse emissions more next year than the Toyota Prius hybrid, despite the little hatchback’s gaudy 52-mpg fuel economy rating.

Sound crazy? Blame math.

The Prius revolutionized the auto industry, but it sells in puny numbers compared with full-size pickups, America’s top-selling vehicle class. That’s just one of the factors that makes the fuel economy race among pickups like the new Ram, Silverado and GMC Sierra vital to reducing fossil fuel use and the emissions associated with climate change.

In addition, a 1 mpg improvement by a high-consumption vehicle like a pickup saves more fuel than a bigger increase in a high-efficiency vehicle.

Read more: Fuel-saving tips

Examples from U.S. Department of Energy research:

Assuming the same distance driven annually, a 1-mpg increase in combined city/highway fuel economy from 16 to 17 mpg saves as much gasoline as improving from 25 to 27.5 mpg or 35 to 40 mpg.

That 1-mpg improvement in fuel economy from 16 mpg to 17 mpg also saves more gasoline than a 6-mpg improvement from 46 to 52 mpg when driving 12,000 miles a year. (12K miles a year is the standard used for window-sticker efficiency figures. You can calculate fuel consumption for other vehicles and distances here.)

Customers replacing a 2009 5.3-liter V8 Silverado with a 2019 Silverado using a new 5.3L V8 and six-speed transmission will save 4.4 million gallons a year for every 100,000 pickups sold. Upgrading to the optional eight-speed transmission increases the savings even more, thanks to the eight-speed’s 19-mpg combined city/highway rating.

People who replace a 46-mpg 2009 Prius with a 52-mpg 2019 Prius and drive the same 12,000 miles a year will save 3 million gallons of fuel per 100,000 vehicles. That’s 35 percent less fuel saved than the same number of Silverados.

And those figures are for “just” 100,000 pickups. Chevy sold 585,000 Silverados last year. Ram sold 556,000 pickups, Ford 896,000 F-series and GMC 217,000 Sierras. Toyota sold 108,000 Priuses.

A hundred thousand here, a hundred thousand there. Pretty soon you’re talking about real numbers.

“Fuel economy is a top priority,” 2019 Silverado global vehicle performance manager Mike Strickhouser said. “It’s critical, to the program and to our customers.”

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The Ford F-150 started the pickup tech race when it traded a traditional steel body in favor of aluminum and added small turbocharged engines four years ago.

Automakers are using every trick in their bags to reduce pickups’ fuel consumption. The new pickups use technologies pioneered by hybrids like the Prius, including engines that shut off when idling or coasting and grille shutters to reduce aerodynamic drag.

More capability using less fuel

“Pickup owners expect their new truck to do everything their current truck does, only better,” Ram engineering chief Rob Wichman said. “The new Ram 1500 delivers just that, with greater fuel efficiency and more capability."

The Ram 1500 even has a 48-volt starter-generator, an advanced feature previously only seen on high-end luxury models. Engineers mounted an extra battery in the pickup cab’s rear wall to power the system, which helps the engine start smoothly when it’s stopped at a traffic light. It also aids in acceleration and keeps the air conditioning and lights running smoothly when the engine shuts off.

Lightweight materials, new engines and engine tech abound in the ’19 pickups. GM’s Silverado and Sierra have an amazing valve train that allows V8 engines to run on all eight cylinders, a single cylinder or anything between. The Ram and Chevy V8s scored nearly identical EPA ratings using technologies as different as night and day. That means we can expect greater fuel savings as automakers stack the systems in future vehicles.

The Silverado will also offer a new 2.7L turbocharged four-cylinder engine — small by the standards of full-size pickups, but powerful with 310 hp — that delivers good driveability and a combined city/highway fuel economy rating of 21 mpg in EPA tests.

The Silverado and Ram will add diesel engines next year. Expect class-leading highway fuel economy ratings of at least 30 mpg for both, as the battle to build the most efficient full-size pickup intensifies.

Contact Mark Phelan: mmphelan@freepress.com or 313-222-6731. Follow him on Twitter @mark_phelan.