2019 Mercedes-Benz GLS450 4matic Fuel Economy

18 MPG combined is what you can expect in the world of full-size, three-row luxury SUVs. The 2019 Mercedes-Benz GLS450 4matic, with its smooth 3.0L inline-6, is a practical choice for buyers who want space, reliable towing capability, and the Mercedes-Benz brand more than great fuel efficiency. This isn’t a vehicle for those seeking economy; it’s for families who need maximum utility and are willing to pay for premium features and performance.

City and highway performance

The GLS450 4matic emphasizes confident acceleration and a comfortable ride over fuel savings. Expect 16 MPG in city driving, a number that reflects stop-and-go traffic and the vehicle’s weight. On the open highway, this improves to 22 MPG, thanks to the smooth-shifting 9-speed automatic transmission’s ability to keep the engine within its most efficient operating range at cruising speeds. The standard 4MATIC all-wheel drive system adds security in bad weather, but it also increases the GLS450’s fuel consumption compared to lighter vehicles.

Annual fuel cost

The EPA estimates the annual fuel cost for the 2019 Mercedes-Benz GLS450 4matic at $3,200. This is based on driving 15,000 miles per year, with a mix of city and highway driving, and using national average fuel prices. Individual fuel costs will vary based on driving habits and local gas prices, but this number is a benchmark for comparing the GLS450’s running costs to other vehicles. Consider that this the approximate cost to own this vehicle.

Real-world expectations

While EPA estimates are a useful benchmark, real-world fuel economy can change. Factors such as driving style, weather, and cargo weight all affect the GLS450’s fuel efficiency. Drivers who accelerate quickly will likely see lower numbers than the EPA estimates, while those who accelerate smoothly and maintain consistent speeds on the highway may achieve slightly better results. Proper tire inflation and timely oil changes can also help maximize fuel efficiency. Even under optimal conditions, expecting much better mileage than the EPA estimates is unrealistic.

How it compares

The GLS450 is in a competitive segment where fuel economy, though not the main concern, is still a consideration. The BMW X7 xDrive40i, another choice, achieves similar numbers, around 20 MPG combined. The Lexus LX 570, known for its ruggedness, falls behind with a combined MPG in the low teens. The Volvo XC90 T6 offers a slightly more efficient alternative, rated around 22 MPG combined, but lacks the size and towing capacity of the GLS450. The Lincoln Navigator lands around 18 MPG combined. The GLS450 offers competitive fuel economy within its segment without losing the performance and capabilities that buyers expect. For more, check out GLS450 MPG across all years.

Tips to maximize efficiency

The GLS450 offers drive modes that affect fuel consumption. Use “Comfort” or “Eco” mode for daily driving, as these modes typically prioritize fuel efficiency by adjusting throttle response and transmission shift points. Sport mode is best for when maximum performance is needed.

Check your tire pressure. Underinflated tires increase rolling resistance, which impacts fuel economy. Check your tire pressure regularly and inflate them to the recommended levels found on the sticker inside the driver’s side doorjamb.

Avoid idling. If you anticipate waiting for more than a minute, turn off the engine. Modern engines restart quickly, and idling wastes fuel.

Reduce aerodynamic drag. Remove roof racks and cargo carriers when not in use, as they increase wind resistance and reduce fuel economy, especially at highway speeds. Explore all Mercedes Benz fuel economy data to see how other vehicles compare.