When shopping for a diesel truck in 2025, one of the biggest concerns for buyers—whether fleet owners or weekend warriors—is fuel economy. Diesel trucks are known for their torque and durability, but fuel efficiency can vary widely depending on the make, model, and purpose of the vehicle. Fortunately, manufacturers are investing in smarter, more efficient engines without compromising on performance.

Why Fuel Economy Matters in Diesel Trucks

Fuel efficiency isn't just about saving at the pump. It affects:

1. Total cost of ownership

2. Carbon footprint

3. Towing efficiency

4. Engine longevity (less strain means longer life)

As diesel prices remain high in many regions, opting for a fuel-efficient diesel truck can result in thousands of dollars saved annually.

Top Diesel Trucks with Best Fuel Economy in 2025

1. 2025 Chevrolet Silverado 1500 Duramax

1. EPA-Estimated MPG: 24 city / 29 highway

2. Engine: 3.0L Duramax Turbo-Diesel I6

3. Towing Capacity: Up to 13,300 lbs

The Silverado 1500 with its updated Duramax engine continues to lead the pack in fuel economy for full-size pickups. With its smooth 10-speed transmission and intelligent fuel management system, this truck blends power with impressive efficiency.

2. 2025 GMC Sierra 1500 Duramax

1. EPA-Estimated MPG: 23 city / 29 highway

2. Engine: 3.0L Duramax Turbo-Diesel I6

3. Towing Capacity: Up to 13,000 lbs

GMC’s luxury take on the Silverado, the Sierra 1500, delivers nearly identical efficiency with a more upscale interior and smoother ride. It’s ideal for those looking to balance fuel savings with comfort and style.

3. 2025 Ram 1500 EcoDiesel (Final Edition)

1. EPA-Estimated MPG: 22 city / 32 highway

2. Engine: 3.0L V6 EcoDiesel

3. Towing Capacity: Up to 12,560 lbs

Although Ram is phasing out the EcoDiesel in favor of hybrid and EV options, the 2025 final edition is one of the most fuel-efficient diesel trucks ever made. It’s a top pick for those wanting a light-duty diesel that excels in both city and highway conditions.

4. 2025 Ford F-150 Power Stroke Diesel (Limited Availability)

1. EPA-Estimated MPG: 22 city / 30 highway

2. Engine: 3.0L Power Stroke Turbo Diesel V6

3. Towing Capacity: Up to 11,500 lbs

Ford has scaled back availability of its diesel engine in the F-150 lineup, but the Power Stroke remains a solid performer for those who can find one. Its smooth acceleration and strong MPG numbers make it a desirable choice.

Also read: Why Does My Diesel Exhaust Smell Sweet?

Best Heavy-Duty Diesel Trucks for Fuel Efficiency

5. 2025 Ford Super Duty F-250/F-350 (6.7L Power Stroke)

1. Estimated MPG (Real-World): 15–18 combined

2. Towing Capacity: Up to 37,000 lbs (F-450)

While EPA does not rate heavy-duty trucks, real-world testing puts the Ford Super Duty lineup at the top. With a class-leading Power Stroke diesel and smart turbocharging, the F-250 and F-350 offer impressive fuel economy for their size and capability.

6. 2025 Ram 2500 Cummins Turbo Diesel

1. Estimated MPG: 14–17 combined

2. Engine: 6.7L Cummins I6 Turbo Diesel

3. Towing Capacity: Up to 20,000 lbs

Known for its legendary durability, the Ram 2500 with the Cummins engine is not only a towing powerhouse but also surprisingly fuel-efficient for its class. Many fleet operators prefer it for long-term savings.

Read more: How to Increase Fuel Mileage on a Diesel Pickup

What Impacts Diesel Truck Fuel Economy?

Several factors determine how efficiently a diesel truck burns fuel:

1. Payload and towing: Heavier loads = lower MPG

2. Tire size and gear ratios

3. Turbocharger efficiency

4. Driver habits and idling time

5. Terrain (hills, off-roading reduce fuel economy)

Many modern trucks now come with drive modes (e.g., Eco, Tow/Haul) to optimize fuel use depending on the conditions.

Final Thoughts

If you’re looking purely at numbers, the 2025 Ram 1500 EcoDiesel takes the crown for best highway mileage at 32 MPG. For full-size performance and availability, the Chevy Silverado 1500 Duramax is a strong runner-up, offering nearly 30 MPG and excellent towing capacity.

For heavy-duty haulers, the Ford Super Duty 6.7L Power Stroke strikes a balance between power and efficiency—especially impressive given its size.

When choosing your next diesel truck, weigh fuel economy alongside features like towing needs, long-term durability, and total cost of ownership. You might be surprised at how much you can save over time by going with the right engine and configuration.

FAQs

Q: Which 2025 diesel truck has the best MPG overall?
A: The 2025 Ram 1500 EcoDiesel offers the best overall fuel economy at up to 32 MPG highway.

Q: Are diesel trucks more fuel-efficient than gas trucks?
A: Yes, diesel engines generally offer better fuel economy and torque than gas engines, especially under load.