For close to a decade, Mazda said it would bring its latest generation of diesel engine, Skyactiv-D, to the United States. And for most of that time, it said that engine would appear in the Mazda6. Last year Mazda finally brought us the engine in the CX-5, and it looks like this year, the 6 will finally get it, too.
This seems to be the case based on a CARB certification posted on January 31 specifically for the midsize family sedan. The CX-5, in both front-wheel- and all-wheel-drive variants, is listed in a different certification, so it's not a case of a blanket certification for every vehicle the engine could appear in this year. As expected, the document lists the 6 as having a 2.2-liter turbocharged engine with a six-speed automatic, though it doesn't say whether the model is front-wheel-drive or all-wheel. Either is certainly possible, since all-wheel drive, in particular with the diesel, is available in overseas Mazda6s. Like in the CX-5, the engine will probably make 168 horsepower and 290 pound-feet of torque.
While this certification tells us the diesel 6 will probably launch this year as a 2021 model, we're left to estimate the reveal date. Midway through the year, or possibly at the start of the next auto show cycle would seem likely, which would coincide with a model year update. Mazda has stated it will only be offered on the top-tier Signature trim, which starts at $36,345 with the standard turbocharged gasoline 4-cylinder. Looking at the price difference between a turbocharged Mazda CX-5 Signature with all-wheel-drive and the diesel CX-5, the price difference is about $4,000, so it would seem reasonable to expect the Mazda6 diesel to ring in at about $40,000.