Chevrolet's diesel-powered 2018 Equinox compact SUV has been rated by the Environmental Protection Agency to achieve 39 miles per gallon in highway driving, General Motors has announced.

The EPA rates the diesel Equinox at 28 mpg in city driving and 32 mpg combined. The all-wheel-drive diesel Equinox provides the same city and combined ratings, as well as 38 mpg in highway driving.

The diesel Equinox, arriving at dealerships now, has a range of 577 miles, GM announced. It's powered by a 1.6-liter Ecotec turbo-diesel that makes 137 horsepower.

The engine, which is sourced from a GM plant in Turino, Italy, also powers diesel variants of the Chevrolet Cruze, Cruze Hatch, and GMC Terrain. The engine is the third light-duty diesel GM has added to its lineup.

"Diesel provides plenty of benefits for customers who drive a lot of miles," said Dan Nicholson, GM's vice president of global propulsion systems, at a briefing in Santa Monica, Calif. "It may be one of the best kept secrets among diesel fans."

GM expects commercial fleets with a specific driving profile to consider the diesel Equinox. An ideal fleet vehicle would drive at least 20,000 per year of mostly highway miles, Nicholson said.

GM also offers the Chevrolet Cruze sedan with a diesel powerplant, which is EPA rated at 52 mpg on the highway and 37 mpg combined. 

GM now offers 12 diesel-powered vehicles on three engine platforms, including the Duramax 2.8-liter that powers the Chevrolet Express and Colorado, as well as GMC Savana and Canyon; and the Duramax 6.6-liter that powers the Silverado HD and Sierrra HD.

In 2018, GM will begin selling its medium-duty Class 4/5 truck that will also be powered by the Duramax 6.6-liter engine.