Diesel Prices Are Rising, But GM Still Backs Its Duramax
Diesel prices are skyrocketing everywhere, and that means filling up a diesel pickup is starting to sting. So it’s no surprise that GM CEO Mary Barra got grilled during the company’s Q3 2026 earnings call about whether these sky-high diesel costs might scare off buyers.
Barra’s answer was unexpected. She says GM’s Duramax diesels are still cheaper to own, even as diesel prices rise. She argues that better fuel efficiency can offset the higher fuel costs. But does using less fuel really mean you’ll spend less over time?
Chevrolet
The Numbers Give GM Some Ground to Stand On
GM didn’t spell it out, but let’s be real: they’re talking about the 3.0-liter LZ0 turbo-diesel inline-six going up against Ford’s 3.5-liter PowerBoost V6 hybrid and Toyota’s 3.4-liter i-Force Max V6 hybrid.
GM Authority analyzed the numbers, looking at four-wheel-drive fuel economy and 2026 base prices. The Duramax comes out ahead, but the difference from Ford’s hybrid isn’t very large.
The Duramax pulls off 24 mpg combined, just a hair better than Ford’s 23 mpg and noticeably ahead of Toyota’s 20 mpg. It’s also the cheapest to get into, so GM isn’t just blowing smoke here.
However, the hybrids are much more powerful, obviously. Toyota’s system produces 437 hp and 583 lb-ft of torque, Ford’s offers 430 hp and 570 lb-ft, while GM’s diesel has 305 hp and 495 lb-ft. Those are sizable gaps, which could matter if you want better on-road performance and lower-end grunt.
Zac Palmer
Maintenance Costs Could Change the Equation
Of course, mpg and sticker price are just the tip of the iceberg. Scheduled maintenance can sneak up and take a bite out of your wallet over the years. Don’t forget, diesel trucks need diesel exhaust fluid too. Sure, DEF is cheap if you buy it by the jug, but it’s still a cost hybrid owners can mostly ignore.
So, GM’s case holds water if you’re only looking at fuel economy. But the real answer to which truck is cheaper to own? That depends on everything from fuel prices and how much you drive to maintenance, where you drive, and how long you hang onto your truck.
Chevrolet
