22 MPG combined is acceptable fuel economy for the 2025 Chevrolet Suburban 4WD with the 3.0L Duramax diesel. No one buys a Suburban expecting Prius-like efficiency. This is a full-size SUV designed to haul families, cargo, and trailers, and while the Duramax offers a blend of power and relative efficiency, physics ultimately dictate the outcome. This is a tool, not a toy, and its fuel consumption reflects that.

City and highway performance

The EPA estimates the Suburban 4WD Duramax at 20 MPG in the city and 26 MPG on the highway. These figures highlight the diesel’s strength: highway cruising. Its abundant torque allows it to maintain speed effortlessly, even when loaded, contributing to the impressive highway number. The city figure, while lower, is still respectable for a vehicle of this size. Expect the city MPG to fluctuate significantly based on driving style and traffic conditions. Stop-and-go driving will reduce fuel economy, while a relaxed approach will yield better results.

Annual fuel cost

The EPA estimates the annual fuel cost for the 2025 Chevrolet Suburban 4WD 3.0L Duramax to be $2,550. This figure is based on driving 15,000 miles per year and using the national average fuel price. As diesel fuel prices fluctuate, this number will vary, of course. However, $2,550 provides a benchmark for understanding the cost of ownership associated with fueling this large SUV. It’s important to remember that individual driving habits and local fuel prices will ultimately determine your real-world spending.

Real-world expectations

While the EPA estimates provide a useful baseline, real-world fuel economy can vary considerably. Factors like driving style, terrain, load, and even tire pressure can influence your MPG. Owners who frequently tow or carry heavy loads should expect lower fuel economy than those who primarily use the Suburban for commuting. Similarly, driving in hilly or mountainous areas will negatively impact MPG compared to flat terrain. Aggressive driving, characterized by rapid acceleration and hard braking, will also significantly reduce fuel efficiency.

Expect to see numbers within a few MPG of the EPA estimates under normal, mixed-use driving. Some drivers may even exceed the highway rating on long road trips, while others may struggle to reach the city figure in congested urban environments.

How it compares

Compared to its gasoline-powered counterparts, the 3.0L Duramax offers a fuel economy advantage. The 5.3L V8 Suburban 4WD, for instance, achieves only 16 MPG combined. Even Ford’s Expedition, equipped with its EcoBoost turbo V6, struggles to match the Duramax’s efficiency, delivering only around 19 MPG combined in 4WD guise. The larger gasoline engines have better acceleration, and in some instances, overall towing capacity.

Among diesel competitors, the Duramax edges out the Nissan Armada with its 5.6-liter V8, which achieves a measly 14 mpg combined as that engine is known for its lack of effeciency. For Suburban buyers prioritizing fuel economy without sacrificing capability, the Duramax diesel remains the clear choice. You can see all Chevrolet fuel economy data on our site.

Tips to maximize efficiency

Consistent and gentle acceleration is key to maximizing fuel economy with the Duramax diesel. Avoid aggressive throttle inputs, allowing the engine’s abundant torque to pull the Suburban forward smoothly. This engine rewards a patient approach to driving.

Maintain proper tire inflation, and ensure your tires are made for high-quality touring. Underinflated tires increase rolling resistance, decreasing fuel economy. Check your tire pressure regularly, especially before long trips. This is especially important with a large vehicle of this type frequently being used for family road trips.

Reduce unnecessary weight. Carrying extra cargo, especially heavy items, increases the amount of energy required to move the Suburban. Remove any unnecessary items from the vehicle to improve fuel economy. This applies to both cargo inside the cabin, and weight in things like aftermarket roof racks where areodynamic drag can have a big impact on long highway drives.

Minimize idling time. Diesel engines, while generally more efficient than gasoline engines, still consume fuel while idling. Avoid excessive idling, particularly in cold weather, as it significantly reduces fuel economy. Turn off the engine when stopped for extended periods.

Consider the drive mode. Suburbans equipped with adjustable drive modes often include an “Eco” or “Efficiency” mode. Select this mode to optimize engine and transmission settings for maximum fuel economy. It’s a simple change that can make a difference, especially around town. Interested in SUBURBAN MPG across all years? Find it right here.