STERLING HEIGHTS, MI –General Motors today unveils its redesigned-for-’15 lineup of Chevrolet and GMC large SUVs, a product range counting five models and featuring more available content, greater elbow room, higher fuel economy and expressive styling almost certain to make them a hit out of the gate.

The light trucks, which retain a sturdy but redesigned body-on-frame structure from the auto maker’s large pickups, go on sale in the first quarter of next year and launch into a market shrunken greatly from its heyday of the previous decade. But the SUVs remain popular with Americans seeking the combination of cargo space and towing and hauling capability found in few other vehicles.

As a testament to the popularity of GM’s big SUVs, the average age of those vehicles on U.S. roadways today is 11 years. It’s been seven years since their last full redesign, and buyers are chomping at the bit for new ones, says John Schwegman, GM’s truck product and pricing chief.

“It is very ripe for returning customers,” he says during a recent sneak peek of the trucks here. “We think we’re in a really good spot to capture those folks as they come back in.”

GM Chief Financial Officer Dan Ammann says the new Chevy Tahoe and Suburban will resonate again with consumers.

“The Chevrolet Tahoe and Suburban will continue to be dominant forces in the marketplace and provide great value for our customers,” Ammann says in a statement ahead of simultaneous unveilings of the trucks to the public in Los Angeles and New York.

“This is an important and profitable segment, and we have set the bar high to ensure we provide our customers with great quality and performance.”

The GMC Yukon, Yukon XL and nameplate flagship Yukon Denali will continue to cater to a young, highly educated, affluent consumer seeking more luxury and distinctive styling in their large SUV, says Tony DiSalle, vice president-marketing at GMC.

“We’ve engineered the Yukon and Yukon XL from the ground up, building on a strong legacy of capability to take them to the top of the segment with exceptional refinement and purposeful technology,” DiSalle says. “And when it comes to the tasks people rely on a (large) SUV for, they do it better than ever and with more style.”

A new Cadillac Escalade, which rounds out GM’s portfolio of large SUVs, will be shown next month at a separate event in New York.

Fold-flat second- and third-row seating arguably ranks as the most significant new interior item in the Chevy and GMC versions of the trucks.

Both rows include an available power-folding option, eliminating the most common complaint from owners:  manually removing the bulky, heavy third-row seats of current models and second-row seats that folded but fell short of opening up significantly greater cargo room.

“It’s been our Achilles heel,” admits Jeff Luke, GM’s top truck engineer.

Consider the feature a feather in the cap of GM’s engineers, who pulled off fold-flat capability while retaining a solid rear axle. It does come at the sacrifice of some headroom because the auto maker raised the floor of the SUV slightly, but the trade-off is minimal because other design tweaks add headroom.

Second-row legroom improves 2 ins. (5 cm) and ingress/egress for those passengers becomes easier, too.

The redesign solves another bugaboo of the large SUVs: wind noise. Inlaid doors that now fit into the vehicle frame instead of overlapping onto the roof and pillars cuts wind noise to minimum levels. The SUVs also add triple door seals and an acoustically laminated windshield.

Schwegman says GM’s truck group started fighting for the features as far back as the auto maker’s 2009 bankruptcy, when engineers outfitted top executives with headphones one afternoon to show the difference a few more investment dollars could make.

“We let them listen for themselves and said, ‘Here’s what you have now, and here’s what you could have.’ They were sold,” Schwegman says.

GM also significantly upgrades the trucks’ infotainment options. They now boast an available 8-in. (20-cm) touchscreen radio with Chevrolet MyLink and GMC IntelliLink connectivity to marry up with personal devices for tasks such as hands-free calling and access to Internet radio.

Buyers can get up to six USB ports and six power outlets, including a 110V, 3-prong outlet to give passengers 12 locations for powering and playing personal devices.

Optional DVD players inside the SUVs still flip down from overhead, but carry a slimmer profile and now have Blu-Ray capability. Suburban buyers again can choose dual screens for second- and third-row viewing.

Shoppers also will find more-refined interior materials, and a design meant to be more contemporary and user friendly.

Designers seemingly made use of every available corner for storage, such as upper and lower trays on the inside door panels for first- and second-row occupants’ personal items. Center-console storage accommodates an iPad, and the center console’s motorized touchscreen lifts to reveal lockable storage.

The GMC models, especially the Denali versions, go even further upscale by advancing the brand’s “professional grade” design aesthetic by blending wood, metallic and leather materials with an instrument panel soft to the touch and lots of ambient lighting.

All of the SUVs come with GM’s latest suite of standard and optional safety technologies, such as forward-collision alert, front-park assist, lane-departure warning and adaptive cruise control. Improved braking stops the vehicles sooner, and items such as sensors determining movement and glass breakage, as well as door-lock protectors, make the trucks more theft-resistant.

“Unfortunately, these trucks are a popular target,” Luke says. “We believe these technologies will translate into lower insurance costs.”

Owners also should pay less at the pump; the SUVs feature GM’s Gen 5 EcoTec3 small-block V-8 engines. A 355-hp 5.3L V-8 is standard on the Tahoe, Suburban and Yukon models, while the Yukon Denali receives a range-topping 420-hp 6.2L V-8.

Each engine features gasoline direct injection, variable valve timing, an advanced combustion cycle and wider availability of cylinder deactivation to improve fuel economy.

All the trucks use a GM 6-speed automatic transmission with tap-shift control, a separate mode for towing and hauling, and grade braking.

Fuel-economy figures, as well as pricing, will be released closer to their on-sale date.

The auto maker says ride and handling of the SUV is improved, as well, courtesy of a stronger frame and wide rear stance. Magnetic ride control and real-time suspension damping “read the road” to provide optimum driver control, while wider rear wheels aid cornering and a more responsive electronic power steering system is speed-sensitive.

Exterior styling of the Chevy and GMC models grows more distinct. Both designs are bolder, with the Tahoe and Suburban gaining a new dual-port grille now common to all new Chevrolets and the Yukon line adding more chrome to its crisply sculpted lines.

The SUVs’ exterior designs also diverge farther from those of GM’s large pickups by no longer sharing any sheet metal between the two truck lines.

jamend@wardsauto.com