Fuel economy is the bane of most big SUVs and crossovers, at least the ones without explicit gas-saving technologies factored into their drivetrains. Count the GMC Acadia among those: it was revamped in 2013, but more in styling and in feature content, though the transmission's shift logic was updated.
The Acadia's powertrain still turns in the same gas-mileage numbers it has delivered for the past few years. The highway numbers are acceptable, but the city numbers...they're not great.
The EPA rates the Acadia at 17/24 mpg or 19 mpg combined in front-drive versions, and at 16/23 mpg or 18 mpg combined in all-wheel-drive models. Based on past drives in the Acadia, as well as the nearly identical Chevrolet Traverse and Buick Enclave, we tend to think those figures are a little optimistic. We'd also add the six-speed automatic in the Acadia does provide a wide span of ratios to keep revs low when cruising on the highway.