2018 Audi A6/A7: New Design, More Tech This global mid-sizer is essential to Audi's well-being.

What It Is: Audi’s mid-size sedan and its low-slung brother. Both versions will draw from the design of the recent Prologue family of concept cars. They’ll feature an entirely new user interface, similar to the one in the upcoming A8.

Why It Matters: The A6 is essential to the brand’s well-being, with higher profit margins than the similarly high-volume A3 and A4. Plus, the car has global appeal that stretches from Europe to the U.S. and China.

Platform: Like the 2018 A8, the next A6 and A7 models are based on Audi’s modular-longitudinal MLB Evo architecture. This highly flexible platform allows for front- and four-wheel drive and will offer a bevy of telematics and assistance systems. And let’s not forget the body variations, of which there will be four: sedan, long-wheelbase sedan for China, Avant wagon/Allroad (available outside the U.S.), and A7 hatchback.

Powertrain: The base A6 will get a 2.0-liter turbo four, with a turbocharged V-6 optional on the A6 and standard on the A7. The S6 and S7 get a twin-turbocharged V-6 with around 400 horsepower, while the RS6 and RS7, expected for late 2018 or 2019, keep the twin-turbocharged V-8. Down the road, there will be mild hybrids, a plug-in hybrid, and a diesel for the U.S.

What Might Go Wrong: Buyers in this (and every) segment are migrating to SUVs. The A6 needs to tempt people with its interior and exterior designs, high-quality materials, and performance.

Estimated Arrival and Price: Mid-2017 for the A7, fall 2017 for the A6; both will keep their current pricing position, beginning just below $50,000 for the A6 and below $70,000 for the better-equipped A7.