GM released this "preview" image of the all-new 2017 Buick LaCrosse. The new LaCrosse will be unveiled in Los Angeles next month. Source: General Motors.

It's no secret that General Motors (GM -0.27%) is in the midst of a massive effort to overhaul its Cadillac brand. But now it's looking like Buick might be getting some attention, too.

GM this week released a sneak preview of the all-new-for-2017 Buick LaCrosse, along with a few details of its next-generation premium sedan.

We'll have to wait until the new LaCrosse is unveiled (next month) before we know all the details. But what we do know suggests that the whole Buick brand might be getting a rethink -- and that could be a very good thing for GM.

The new LaCrosse should be a step up from the current car
So what we know about the new-for-2017 LaCrosse? We know that it will get an all-new look, with a grille that looks a lot like the one on the stunning Buick Avenir show car. In fact, GM said this week that that grille is "the new face of Buick," and all Buicks will adopt the look by 2018.

The Buick Avenir Concept was built on the rear-wheel-drive luxury-car platform developed for the big new Cadillac CT6 sedan. For now, it's just a show car, but executives have hinted that GM could produce it in a few years as a flagship for the Buick brand. Source: General Motors.

We also know (or at least strongly suspect) that the new LaCrosse will share underpinnings with the all-new 2016 Chevrolet Malibu sedan that is set to come to market shortly. That's a good thing: Not only is the new Malibu roomy, it's 300 pounds lighter than the outgoing version of the Malibu. GM says that the new LaCrosse will also be lighter than the model that it will replace.

The LaCrosse is likely to be a bit longer than the Malibu. That length should give it excellent rear-seat room -- an important selling point in China, where well-heeled car owners often ride in the back and let hired drivers contend with traffic. 

GM promises that the new LaCrosse will not only be lighter than the current car, but that it will also provide "a more dynamic driving experience." It'll have a sophisticated five-link rear suspension, and GM promises a "more responsive ride, while taking Buick's signature quietness to a new threshold."

It looks like an overhaul of Buick is under way
GM has pitched Cadillac directly against the big-name German luxury brands. Cars like the Cadillac ATS and CTS sedans almost seem to be more German than their rivals in some ways, with taut sporty handling and impeccable interiors.

Buick is aiming in a very different direction. GM often cites Lexus, Toyota's (TM -1.12%) luxury brand, as a benchmark for its Buicks. Its press release teasing the new LaCrosse pointedly compared some new features to those on the midsize Lexus ES sedan. That's typical.

Under the global structure put in place by CEO Mary Barra, Buick is a sibling brand of GM's German Opel subsidiary. The two brands share many (but not all) models, which are sold as Opels in Europe and Buicks in America -- and in China, too.

China is a big part of the Buick story. Buick has long been one of China's best-selling brands. That makes it important to GM -- and GM wouldn't mind if Buick could boost its sales in the U.S. as well.

It looks like GM is going to try to make that happen. Several more new Buicks are coming. A new Buick Regal is likely to appear late next year, following the redesign of its German sibling, the Opel Insignia. A new version of the compact Verano is also in the works.

And it's very possible that GM could decide to start building the Buick Envision here in the U.S. The Envision is a midsize SUV that was introduced earlier this year in China -- and it's selling very well there.

Long story short, GM is giving its old Buick brand a new look and a slew of new products. Will a big sales boost follow? We'll find out.