Engineers have managed to squeeze a few more MPG out of the next-generation 2015 Chevy Tahoe and 2015 Chevy Suburban, with both enjoying non-negligible increases across the board, at least with their standard engines.
That 5.3-liter V8, as a reminder, is rated at 355 hp and 383 lb.-ft. of torque, and in the Bowtie Brand's new suvs will serve up identical EPA ratings of 16 mpg city/23 mpg highway/18 mpg combined; to put those numbers into context, horsepower is up by about 11 percent, torque has increased by more than 14 percent and those fuel-economy marks represent jumps of roughly 7 percent/10 percent/6 percent.
Fuel-efficiency is up in the four-wheel-drive models as well, although with less of an impact, as the 2015 Chevy Tahoe 4x4 moves from 15/21/17 to 16/22/18 and the Suburban 4X4, from the same starting point, ekes out a rise to 15/22/18.
Tow ratings also improve by a bit, with the Tahoe now topping out at 8,600 lbs. (+100 lbs. over the 2014 model) and the Suburban's highwater mark reaching 8,300 lbs. (+200 lbs.).
Said Sheryl Balsley, assistant chief engineer for Small Block engines for GM: “Customers use the Tahoe and Suburban for everything from school runs to towing boats, and we’ve developed a powertrain that delivers greater efficiency without sacrificing the power they expect from a Chevrolet suv. The capability of the engine to instantly switch to four-cylinder mode, for example, improves efficiency when less power is required, but delivers full eight-cylinder power whenever it’s needed.”
And to be clear, that Active Fuel Management system is just part of the picture, as Chevy engineers also helped focus on improving fuel efficiency by deploying direct injection, continuously variable valve timing and a slew of incremental upgrades, ranging from a new oiling setup to a unique positive crankcase ventilation system that is so new that GM is still waiting on the patent.
If that seema like an awful lot of effort for just a few miles per gallon, keep in mind that, at this stage in the game, the latest EPA grades for the 2015 Chevy Tahoe and Suburban translate into some relatively large advantages over the competition. Neither the Nissan Armada nor the Toytoa Sequoia can crack 20 mpg on the highway even in their two-wheel-drive configurations, and the Ford Expedition, which won't get its EcoBoost engine until the next model year, currently sits at 14 mpg city/20 mpg highway/16 mpg combined.