Suburban Chevrolet Cadillac Saab Hummer saw some big changes in the past year. One of them was Hummer: it’s gone. General Motors deep-sixed the brand after a deal to sell it to a Chinese buyer fell through. That shrank the dealership’s name to Suburban Chevrolet Cadillac Saab. But the biggest change was a $4 million renovation that split the dealership into two showrooms–one devoted to the middle-class Chevrolet nameplate and the other shared by the high-end Cadillac and Saab brands.

“Structurally, it’s a complete redo,” says general manager Mike Mosser. “Everything is new, from the service department on up.” The Cadillac/Saab showroom has the elegantly retro look of a Mad Men-era New York ad agency, with imported Italian floor tiles, walnut-stained paneling, glassed-in sales offices, and a gray-and-silver color scheme. The customer waiting area has starkly stylish wood-and-metal magazine racks, marble slab tables, a full coffee bar, and wide, low-slung seating in the style of Mies van der Rohe’s iconic Barcelona chairs–all updated with the inevitable scattering of plasma TVs. The Chevy waiting room’s not quite as well appointed–only one plasma TV, a somewhat less opulent coffee bar, and no marble–but has similarly clean, Ikea-esque lines.

Another innovation is what Mosser calls the Cadillac “Arts and Science Center,” an interactive kiosk about the brand and its history. Cadillac considers it a very big deal and plans to install one in every Cadillac dealership. Suburban, Mosser says, was the first to get one, so GM’s been sending other dealers to Ann Arbor to check it out. In January, they even hosted GM dealers from China, who took time out from the Detroit auto show for a tour.

Recent years have been hard for GM, but Suburban finished out 2010 on a high note. Mosser says sales are up across the board, including a 64 percent spike for Cadillac. He expects that trend to continue this year and estimates that Chevy will account for about 50 percent of sales, Cadillac for 25 percent, Saab for 15, and used cars for the rest.

As for Hummer, Mosser was sorry to see it go. Despite an in-your-face carbon footprint that’s anathema to Ann Arbor’s generally pro-green proclivities, a lot of locals bought them. “Hummer accounted for about 15 percent of our sales,” Mosser said. “You’d be amazed.”

Suburban Chevrolet Cadillac Saab, 3515 Jackson Rd., 663-3321. Mon.- Thurs. 8 a.m.-8 p.m., Fri. 8 a.m.-6 p.m., Sat. 10 a.m.-5 p.m.