Mazda’s long-promised diesel engine finally reached American automotive consumers in the 2019 CX-5 diesel. Alas, its time on our shores was short, with Mazda dropping the engine from its compact crossover just one model year later. But the diesel-drinking engine, known as Skyactiv-D in Mazda parlance, was never supposed to be limited solely to the CX-5. In fact, the engine is still—technically—due to make its way under the hood of the mid-size 6 sedan. Or maybe it isn’t.
To be honest, Mazda never gave us a clear answer when asked about the status of the 6 diesel. Instead, a company spokesperson wrote in an email that Mazda, “cannot confirm when the Skyactiv-D engine will be offered for the [6]. ” If we were gamblers, we’d wager the diesel-powered 6 is no longer in Mazda’s plans for the United States. That said, there’s still some hope the model materializes, as Mazda continues to reserves a space on its consumer site for the 6 diesel.
When—or if—it arrives, the 6 diesel will employ the same turbo-diesel 2.2-liter four-cylinder engine and six-speed automatic gearbox as last year’s CX-5 diesel. Unlike its all-wheel-drive crossover sibling, the 6 diesel all but assuredly channels the engine’s 168-hp and 290 lb-ft of torque to its front wheels.
Unfortunately, the 6 diesel will likely follow in the tire tracks of the CX-5 by being only marginally more efficient and noticeably slower than its gas-powered counterparts. Whereas the standard CX-5’s 187-hp 2.5-liter inline-four earns fuel economy ratings as high as 25 mpg in the city, 31 mpg on the highway, and 28 mpg combined by the Environmental Protection Agency, the most efficient 2019 CX-5 diesel merely managed EPA-ratings of 28 mpg city, 31 mpg highway, and 29 mpg combined.
The diesel’s lesser power also made it slower to 60 mph, and its 9.0-second jaunt to the mile-a-minute mark was down 0.7 second to its naturally aspirated, gas counterpart. The crossover’s available 250-hp turbocharged 2.5-liter four-cylinder, meanwhile, launched the CX-5 to 60 mph in 6.4 seconds.
Of course, it’s possible Mazda’s fiddled with the Skyactiv-D since its debut in the CX-5 and the engine may manage to better the standard 6’s EPA ratings of 26 mpg city, 35 mpg highway, and 29 mpg combined rating by a notable margin. If the company isn’t able to achieve major fuel economy improvements from the diesel engine (the entire selling point of most diesels in passenger vehicles), though, then Mazda may ultimately pull the plug on the U.S.-spec 6 diesel.
After all, the standard four-cylinder is plenty peppy and (relatively) efficient as is. Plus, the sedan’s available turbo four-pot’s 310 lb-ft of torque, which arrives at a low 2,000 rpm, ought to satiate the needs of consumers looking for diesel-like low-end grunt. It seems only a very narrow niche of 6 buyers are looking for the fuel economy of the car’s base engine with the available twist of its optional turbocharged unit.
Officially, the Mazda 6 diesel is still in gestation. However, given Mazda’s non-answer on the status of the model, as well as the limited performance and efficiency gains offered by the CX-5 diesel, we’re wont to believe the 6 diesel is DOA. Nevertheless, we’d love Mazda to prove skeptics, such as us, wrong.
