General Motors has announced official fuel economy numbers for the most extravagant models of its latest full-size pickups: the 2014 GMC Sierra Denali and the 2014 Chevrolet Silverado High Country. Both trucks pack in extra luxury and features, and both are also packing a revised 6.2-liter EcoTec3 V-8 engine under the hood.
Surprisingly, the fuel economy numbers for this big, 420-hp V-8 aren’t too shabby. Rear-wheel drive models get 15 mpg in the city and 21 mpg on the highway; four-wheel drive models get 14 city and 20 highway. That’s an improvement of 2 mpg in the city and 3 mpg highway compared to the old model, but interestingly, it’s the same as the old model’s 5.3-liter V-8 engine.
So, how do they do it? A combination of advanced fuel injection, variable valve timing, and the ability to run on only four cylinders when under light load means the engine burns less fuel. The big trucks also feature fuel saving tricks like electrically assisted power steering, which reduces parasitic drag on the engine. Put short: high tech and less work means better fuel economy, even in a full-size pickukp truck with a 9,800-pound towing capacity.