Best MPG Diesel Truck: For Long-Distance And 4X4 Performance

Best MPG Diesel Truck

The best MPG diesel trucks excel because every component works to save fuel. Efficient engines make strong torque at low rotation per minute. Transmissions keep revs down. Smart gearing, clean aerodynamics, and lighter setups help too. Highway-tread tires reduce rolling resistance. Proper maintenance and quality fuel protect injectors and aftertreatment. Together, these factors raise diesel truck miles per gallon and extend range between stops.

Fuel efficiency saves you money every mile. You buy less diesel, stop less often, and keep maintenance cleaner. Burning less fuel also cuts emissions and your footprint. We focus on diesel truck fuel mileage that works in real life. Ready to lower costs? Explore the latest fuel efficient diesel truck deals and start saving today by finding the best MPG diesel trucks.

Which Diesel Truck Gets The Best MPG?

The top performing diesel trucks according to MPG are;

• Chevy Silverado 1500 3.0L Duramax (2WD): 26 mpg at 75 mph in Car and Driver testing.
• GMC Sierra 1500 3.0L Duramax (4WD): Still the best MPG diesel truck with 4×4.
• HD 2500/3500 diesels (all brands): Approximately 18 mpg on the highway observed in instrumented tests with lighter foot and aero help.

How size and configuration affect diesel truck MPG:

Undisturbed, typical setups vary by drivetrain and class. Use this table as a quick guide to check.

We focus on simple, verified numbers so you can pick the configuration that truly saves fuel.

Best Fuel-Efficient Diesel Truck For Long-Distance Driving

Highway MPG usually beats city MPG in diesel trucks. Steady speeds keep rpm low and turbo boost moderate. Fewer stops mean less idling and wasted acceleration. City driving hurts diesel truck MPG with stop-and-go. For range, highway driving exposes true efficiency. That’s where the best MPG diesel truck shines.

Pick a powertrain that cruises at low rpm in top gear. Choose an efficient automatic with tall final drive. Select 2WD if you don’t need 4×4. Keep weight down. Use highway-tread tires and modest wheels. Add tonneau or aero cover. For diesel truck fuel mileage, skip lifts, racks, and roof cargo.

Engine tech matters. Modern diesels use high-pressure injection, advanced turbos, and cooling to burn lean. Aerodynamics matter; smooth shapes and covered beds cut drag. Weight matters on every hill. For high MPG, we like Chevrolet Silverado and GMC Sierra 1500 Duramax. HD Ram Cummins and Ford Power Stroke also perform well.

Best MPG Diesel 4X4 Truck

Four-wheel drive helps you move, but it costs more in MPG. Driveline parts add weight and friction. A transfer case and front differential add losses. Aggressive A/T tires raise rolling resistance. Small lifts hurt aerodynamics. The same truck as 4×4 returns lower diesel truck MPG than 2WD, keeping revs low and speed steady.

For the best MPG diesel truck with 4×4, we like the Chevy Silverado 1500 and GMC Sierra 1500 with the 3liter Duramax. They balance torque, gearing, and range. For heavier work, Ram 2500 Cummins and Ford F-250 Power Stroke perform very well.

Most Fuel-Efficient Diesel Engine For Trucks

We value diesel engines that turn fuel into work.

• High compression improves thermal efficiency.
• Common-rail injection times multiple small shots for a clean burn.
• Variable-geometry turbos build low-rpm boost.
• Intercoolers keep the charge dense.
• Low-friction internals and smart cooling cut drag.
• Optimized combustion bowls and swirls improve mixing.
• SCR aftertreatment lets engines run lean and clean, protecting diesel truck MPG.

Displacement, turbocharging, and tuning decide results. Small displacement sips at light load. Large engines idle when towing, avoiding high rpm. Turbocharging enables downsizing without losing torque. Tall gearing uses torque to cut revs. Early upshifts and fewer diesel particulate regenerations help. Matching engine size to duty cycle to maximize diesel truck fuel mileage, this helps you get the best MPG diesel truck.

Best MPG 3/4 Ton Diesel Truck

Three-quarter-ton diesels don’t carry EPA labels, so we compare instrumented tests and owner logs. In that world, the frontrunners are the Chevrolet/GMC 2500 Duramax (6.6L), Ford F-250 Power Stroke (6.7L), and Ram 2500 Cummins (6.7L). Unloaded highway results often sit in the 17–20 mpg window, with mixed driving around 15–18 mpg. If you want the best MPG diesel truck in this class, choose the specs that keep rpm low at cruise.

What helps big trucks sip?

• Tall gearing and strong low-rpm torque. Efficient 10-speed automatics.
• Variable-geometry turbos
• High-pressure injection.
• Smart axle ratios.
• Highway-tread tires and correct pressure.
• Aero aids like tonneau covers.
• Choosing lighter options over heavy ones.

These push diesel truck MPG and diesel truck fuel mileage higher.

Most Fuel Efficient Heavy Duty Diesel Truck

Big diesel trucks can still save fuel with the right setup and smart driving.

• Efficiency leaders: Chevrolet/GMC 2500/3500 Duramax 6.6L, Ford F-250/F-350 6.7L, Ram 2500/3500 6.7L.
• Unloaded highway runs often deliver 17–20 mpg when geared sensibly.
• Higher tow and payload ratings add mass, cooling, friction; baseline diesel truck MPG drops.
• Shorter axle ratios (3.73+) raise cruise rpm; towing improves feel but costs fuel.
• Trailer shape and speed dominate drag; tall, blunt fronts at 65–75 mph slash MPG.
• Payload lifts rolling resistance; heavy wheels, tires, tools hurt diesel truck fuel mileage.
• For the best MPG diesel truck under load, pick highway-tread tires, aero aids, and 10-speed autos.

Average MPG For Diesel Trucks

Light-duty diesel pickups average 22–26 mpg combined and 26–30 mpg on the highway. Medium-duty Class 3–6 work trucks often return 8–12 mpg, depending on body and route.

Heavy-duty Class 7–8 tractors typically run 6–8 mpg, while the most efficient long-haul fleets exceed 8–10 mpg and above.

Averages vary because trucks do different jobs. Weight and aerodynamics change with cabs, beds, and upfits. Axle ratios and transmissions set cruise rpm. Duty cycle matters for example, stop-and-go routes, hops, and idling pull numbers down while steady highway cruise raises them. Towing, payload, tire type, terrain, weather, and speed also shift diesel truck MPG and diesel truck fuel mileage.

Diesel Truck MPG Vs. Gas

Diesel engines waste less heat and make more torque. That shows up in real-world MPG and cost.

• Light-duty: diesel half-ton approximately 25 mpg highway, similar gas approx. 20 mpg.
• Heavy-duty: diesel HD approx.18 mpg highway, gas HD approx.15 mpg.
• Cost-per-mile is price per gallon divided by mpg.
• Example: diesel at $4.00 and 25 mpg = $0.16/mi. Gas at $3.50 and 18 mpg = $0.19/mi. Savings approx. $0.03/mi ($3 per 100 miles, approx. $300 per 10,000).
• Savings grow when towing, since gas mpg falls faster.
• For the best MPG diesel truck, keep speed down and tires efficient. Higher diesel truck fuel mileage multiplies every dollar saved.

Diesel Truck Fuel Mileage And Range

Driving range equals tank capacity times fuel economy. Bigger tanks help, but MPG rules the result. Highway numbers are higher than in the city.

Using simple math, range is equal to gallons multiplied by MPG. A 24-gallon half-ton at 29 mpg can reach 696 miles. A 36-gallon three-quarter-ton at 18 mpg covers 648 miles. Towing, lifts, A/T tires, headwinds, and grades reduce diesel truck MPG. The best MPG diesel truck goes far because it keeps rpm low and drag small.

Want maximum range on long trips?

• Keep speed steady and moderate.
• Use cruise when safe.
• Avoid idling at stops.
• Set tire pressures to spec.
• Choose highway-tread tires.
• Remove racks and cargo you do not need.
• Add a tonneau to cut drag.
• Plan fuel stops around reliable stations.
• Use quality diesel to protect injectors and aftertreatment.
• Stay current on maintenance.
• Light right foot.
• Smart gearing.

Together, these strategies raise diesel truck fuel mileage and deliver fewer stops.

What MPG Does A 6.7 Cummins Get?

There’s no official EPA MPG label for the 6.7-liter Cummins in Ram 2500/3500. These are heavy-duty pickups (GVWR > 8,500 lb), so the EPA doesn’t publish estimates. For background, see the EPA’s page “Which vehicles are tested” here: https://fueleconomy.gov/feg/which_tested.shtml.

Real-world data fills the gap. In a year-long test, MotorTrend averaged about 17.5–17.6 mpg in a Ram 2500 Cummins, with a theoretical ~600-mile highway range on one fill. On a 75-mph highway loop across many HD trucks, Car and Driver found diesels averaged ~18 mpg, with a Ram 2500 once touching 20 mpg under favorable conditions.

Your results will vary. Gearing (3.73 vs 3.31), 2WD vs 4×4, tire type/size, lifts, racks, and added weight all change drag and rolling resistance. Towing and headwinds can cut MPG sharply. Speed matters most; higher speeds raise fuel burn quickly. Diesel particulate fluid regenerations and cold weather also nudge numbers. For better mileage, keep speeds moderate, use highway-tread tires, avoid excess weight, and stay on top of maintenance and DEF.

How Many Miles Per Gallon Does A 3.0 Duramax Diesel Get?

We track official ratings placing the 3.0-liter Duramax among the top for diesel truck MPG. In a 2025 Silverado 1500 2WD, Chevrolet lists 23 mpg city and 29 mpg on the highway, with 26 mpg combined. Independent testing backs it up consistently. Car and Driver tests recorded 26 mpg at 75-mph in a 4WD Silverado.

Real-world results shift with setup and daily use. 2WD beats 4×4. Highway-tread tires help. Lifts and racks hurt aero. Towing and headwinds lower numbers fast. The payoff is torque, range, and fewer stops. You get pull at low rpm, making the 3 Duramax a best MPG diesel truck pick for drivers who want strong diesel truck MPG without giving up capability.

How To Increase MPG On A Diesel Truck?

Small habits stack up. Here’s what gives you the most for little effort:

1. Drive smoothly: Aggressive acceleration and late braking can cut mileage 15–30% on the highway and 10–40% in traffic. Keep it steady, use cruise where safe.
2. Watch speed: Drag rises with speed; diesels are happiest at modest highway pace. DOE data shows MPG drops quickly as you climb past the mid-50s.
3. Reduce idling: Beyond 10 seconds, shut it off when practical; idling uses fuel and adds soot load.
4. Mind tire pressure: Proper inflation improves MPG by 0.6–3% on average; under-inflation costs 0.2–0.4% per psi across all four tires. Check monthly.
5. Choose efficient tires: Highway tread leads to less rolling resistance than aggressive all-terrain. Expect approximately a 3% penalty when you switch to ATs of the same size.

Does Premium Diesel Provide Better MPG?

Premium diesel promises cleaner injectors and smoother combustion. But will it boost your diesel truck MPG?

• Standard on-road diesel meeting ASTM D975 is already correct.
• “Premium” usually adds detergents and, sometimes, higher cetane.
• The benefits are deposit control, smoother idle, fewer regenerations and MPG changes are often minimal.
• It is worth it if your OEM recommends TOP TIER, or you run short trips or cold starts.
• Not worth it if the price premium erases tiny MPG gains.
• Track cost-per-mile over 3–5 tanks to see the effects.

The bottom line is, we see quality fuel helps, but your driving habits and maintenance move the needle most in daily use.

Best Mileage Diesel Car Options Compared To Trucks

Diesel cars can beat trucks on pure MPG, but U.S. options are scarce. Standouts typically found used include BMW 328d, Mercedes E 250 BlueTEC, and VW Golf TDI, often delivering 40–50 mpg highway.

Choose a car when you haul light, drive long distances solo, and want lower fuel bills and easier parking. Pick a truck when you tow or need payload, otherwise, a car will outrun the best MPG diesel truck at the pump.

Best Diesel Semi Truck MPG

Efficiency leaders to watch:

• Freightliner Cascadia (Detroit DD15/DT12, aero spec) is consistently between 8–10 and above mpg in optimized long-haul.
• Volvo VNL (D13TC with I-Shift) has strong low-rpm pull and high-mpg cruise capability.
• International LT (A26/Endurant) has light weight and aero packages for competitive economy.
• Peterbilt 579/Kenworth T680 (PACCAR MX-13, automated) has sleek cabs and smart gearing.

Long-haul fleets optimize diesel truck MPG with speed discipline (often 60–65 mph), aero add-ons (roof fairings, chassis skirts, trailer tails), low-rolling-resistance tires, and predictive cruise/control that holds torque in top gear. Downspeed powertrains cut rpm, 6×2 axles and lightweight specs reduce drag and mass. Idle-reduction, tight maintenance, and driver coaching prevent waste. Telematics highlight routes, weather, and fueling strategies to stretch range and lower diesel truck fuel mileage per trip.