Fuel economy and truck ownership have never been natural partners, but the used market holds a handful of pickups that keep the pump bill in check without giving up the bed, the tow rating, or the trail credibility that made you want a truck in the first place. The list below leans on EPA-estimated combined figures, real-world capability, and the practical realities of living with each drivetrain, whether you run gasoline, diesel, or a hybrid. Diesels earn a place because they generally use less fuel than gasoline equivalents, though you pay for that at the pump, since diesel typically costs more per gallon and the pumps are not universally available on long trips.1. Rear-Wheel-Drive Chevrolet Silverado 1500 DieselAmong full-size trucks, the diesel Silverado sets the fuel-economy bar. Rear-wheel-drive 2020 and 2021 models carrying the 3.0-liter turbodiesel six are EPA-estimated at 27 mpg combined, and select configurations are rated for payloads reaching 9,500 pounds. That combination suits a buyer who needs a serious work truck but drives it empty most days. The trade-off is the diesel penalty: sophisticated emissions systems can be costly to maintain, and the highest mpg figures apply to the two-wheel-drive setup, which limits foul-weather and light off-road use.2. GMC Sierra 1500 DieselThe Sierra shares the Silverado's 3.0-liter turbodiesel, and rear-wheel-drive versions are rated at up to 26 mpg combined. It slots in as the near-luxury alternative to the Chevy, though no Sierra comes quite as close as the Silverado to that 27 mpg peak. If you want the same efficient diesel with a more upscale cabin and can live one mpg lighter, this is the pick. The same emissions-maintenance caution applies.3. Ram 1500 HFE EcoDieselRam's HFE was built as a fuel-economy special on the Tradesman platform and sold only as a Quad Cab. With the 3.0-liter EcoDiesel V6 and rear-wheel drive, 2020 through 2022 examples earn an EPA-estimated 26 mpg combined while making 480 pound-feet of torque, with towing rated above 8,000 pounds. Seating for up to six makes it a genuine family-and-work option. The narrow build years and diesel upkeep are the catches.4. Ford F-150 DieselFord offered the F-150 with a 3.0-liter turbodiesel for a limited period, and it returned an EPA-estimated 25 mpg combined. It came in crew-cab form only, seating up to six, so it works well for anyone hauling people and gear over long highway stretches. Because production was short, clean examples are harder to find, and the diesel service costs weigh against the fuel savings.5. Ford F-150 PowerBoost HybridIf you would rather skip diesel altogether, Ford's PowerBoost hybrid teams a 3.5-liter twin-turbo V6 with an electric motor fed by a battery pack, good for up to 430 horsepower and 570 lb-ft of torque. It matches the diesel at 25 mpg combined and adds a feature no other truck here offers: it works as a mobile power generator, a real draw for job sites and base camps. That setup was limited to certain crew-cab builds, so your body-style choice is narrow.6. Chevrolet Colorado DieselFor mid-size buyers, certain 2016 through 2018 Colorados with the 2.8-liter turbocharged diesel inline-four and rear-wheel drive carry an EPA estimate of up to 25 mpg combined. The engine makes 369 lb-ft of torque and tows up to 7,700 pounds. These diesel trucks were offered exclusively as crew cabs seating five, so the cabin stays usable for a family. As with every diesel here, the emissions hardware adds cost over time.7. GMC Canyon DieselThe Canyon is mechanically and largely visually the twin of the Colorado, and the 2018 diesel achieves 25 mpg combined with an EPA-estimated range of 525 miles. The Colorado edges it by a small margin in fuel consumption, but the Canyon answers with a more premium cabin; the Denali trim adds front seats that heat and cool along with wireless charging. The 2018 example noted here is rear-wheel drive, so plan around that if you want traction help.8. Jeep Gladiator EcoDieselThe Gladiator is the pickup version of the Wrangler, which makes it the most trail-ready truck on this list. Fitted with the 3.0-liter EcoDiesel turbo-diesel six and four-wheel drive, it returns 24 mpg combined and tows up to 6,500 pounds. It is the choice for wheelers who want removable doors and a folding windshield with diesel range on the highway. Payload is modest at 1,350 pounds, and diesel maintenance again applies.9. Hyundai Santa CruzThe Santa Cruz breaks from the body-on-frame crowd. Built on a unibody platform shared in spirit with crossovers, it runs a 2.5-liter four-cylinder on gasoline for 23 mpg combined in the 2023 model, and even that figure outperforms most larger trucks at the pump. This is a truck aimed at owners who want a usable bed for lighter duty, such as camping gear and trailhead runs, rather than heavy hauling, a read that Ian Wright backs up. It offers a refined, car-style cabin and a 1,753-pound payload, but towing tops out at 3,500 pounds.10. Ford Maverick HybridThe Maverick is the most fuel-efficient pickup you can buy new, and its hybrid drivetrain reaches an EPA-estimated 37 mpg combined. It is a compact trucksized closer to a late-1990s Ranger or Dodge Dakota than to anything in the current mid-size class, and it shares its platform with the Ford Escape. That makes it ideal for the buyer who wants truck utility in a rig that parks like a car. The interior runs tighter than a Ranger or F-150, and hybrid Mavericks tow far less than the full-size options; the EcoBoost version with the right towing package is rated to pull up to 4,000 pounds.How to ChooseStart with your fuel of choice. A diesel Silverado, Sierra, Ram HFE, Colorado, or Canyon rewards high-mileage drivers with strong combined numbers and torque, but only if you accept costlier emissions upkeep and less convenient fueling. The F-150 PowerBoost and Maverick hybrid keep you on gasoline while cutting consumption, with the Maverick winning outright on economy and the PowerBoost adding onboard power. If your priority is the trail, the Gladiator EcoDiesel is the only genuine rock-crawler here, while the unibody Santa Cruz suits campers and light-duty haulers who value ride comfort over maximum capability. Match the drivetrain to how you actually drive, and the fuel savings follow.