2026 Mercedes-Benz GLS 450 4MATIC full-size luxury SUV, including city vs highway fuel economy and performance: 

🚙 2026 Mercedes-Benz GLS 450 4MATIC — Overview

Engine & Drivetrain

• 3.0 L turbocharged inline-6 with mild-hybrid (EQ Boost). 

• Horsepower: ~375 hp. 

• Torque: ~369 lb-ft. 

• Transmission: 9-speed automatic. 

• Drivetrain: 4MATIC all-wheel drive (standard). 

This setup balances strong performance for a large SUV with a mild-hybrid system that helps fuel economy and responsiveness. 

⛽ Fuel Economy — City & Highway

EPA Estimated Fuel Economy (2026 GLS 450 4MATIC):

• City: ~19 mpg

• Highway: ~24 mpg

• Combined: ~21 mpg

So in everyday driving:

• City: fuel economy stays around the high-teens — typical for a large AWD SUV. 

• Highway: economy improves to the mid-20s as cruising speed and mild-hybrid assist help efficiency. 

This mirrors the EPA numbers carried over from recent model years, as official 2026 figures haven’t shifted significantly. 

📊 Performance & Capability

• 0–60 mph: ~5.8 sec (approx. typical). 

• Fuel tank: ~23.8 gallons. 

• Towing capacity: up to 7,700 lbs when properly equipped. 

• Seating: room for up to 7 passengers with third-row option. 

This makes the GLS 450 a strong choice for families and towing with highway cruising comfort. 

📌 Summary — 2026 GLS 450 Fuel Economy

What this means:

• On urban routes and stop-and-go traffic, expect around 19 mpg. 

• On steady highway trips, efficiency improves toward 24 mpg. 

These figures are typical for a large luxury SUV with AWD and a turbo/mild-hybrid six-cylinder engine. 

If you want, I can break down real-world range estimates based on these city/highway figures and typical fuel tank size.