The redesigned LaCrosse is expected to arrive at Buick dealerships next year.
Pricing and launch timing were not announced.
A new grille design inspired by the Buick Avenir concept gives the LaCrosse a more contemporary look and is calculated to make the sedan more appealing to younger buyers.
"It's a face all Buick models will adopt by 2018," Buick said in a statement.
A five-link rear suspension will provide a more "responsive ride," Buick said.
Technical specifications will be announced later.
The 2016 LaCrosse is on sale now at Buick dealerships with several upgrades for the new model year.
They include an updated IntelliLink system with a new display screen and two USB ports and optional 20-inch wheels on premium all-wheel-drive models.
New exterior colors include Dark Sapphire Blue Metallic and Graphite Gray Metallic.
Edmunds says: Car shoppers making plans for next year may want to include the 2017 LaCrosse on their lists, since it promises to be a striking departure from the current model.