GMC Sierra Denali Loses Bump, Keeps Grind

BOYNE FALLS, MI – There’s an 8-mile (13-km) stretch of state highway leading to one of Michigan’s most popular 4-season resorts where, due to the region’s intense freeze-thaw cycle, concrete belts under the asphalt have degraded over the years to create Texas-size buckles in the road.

In a small car or sedan at 55 mph (89 km/h), the buckles generate a rhythmic ba-bump!, ba-bump!, like going up the first hill of a rollercoaster. In others, such as the long-wheelbase pickups and SUVs favored by vacationers and locals alike here, it feels less like an amusement-park ride and more like atmospheric reentry.

But not in the ’16 GMC Sierra Denali 1500, a large pickup riding on the latest iteration of General Motors magnetic-ride control active-suspension technology.

Previously reserved for high-end GM sports cars such as the Chevy Corvette and notably sold to Ferrari for its 458 Italia, MRC uses sensors to “read” the roadway for changes, such as the bone-jarring buckles here, a railroad crossing or the chatter bumps that can develop on gravel roads.

Electronically controlled shock absorbers, which replace conventional mechanical ones, respond to the changes with split-second damping-rate adjustments. The shocks are filled with magneto-rheological fluid containing minute iron particles, which under the presence of a magnetic charge, align to provide damping resistance, according to GM.

According to our backsides, it’s a technological revolution in fullsize pickup comfort and elevates the Sierra Denali’s balance between ride and handling to the head of the class among Detroit’s truck sellers.

The technology nearly eliminates freeway hop, or that big bounce from the rear end as the suspension rebounds after a bump at highway speeds.

The Sierra Denali corners precisely, too, as the shocks tighten to sports-car stiffness in reaction to steering inputs. But since the system is constantly adjusting between firm and pliable, the sport-like handling does not come at the expense of overall ride quality.

MRC also gives drivers more confidence while trailering or carrying a heavy load, because the sensors detect the extra weight and the truck applies another calibration to control undesirable motions the extra mass can create.

At the end of the day, it delivers passengers to their destination less road-weary, so they can snap on a set of snow skis or jump behind the wheel of a fishing boat without stopping to catch their breath. For the contractor who spends all day driving between job sites, it delivers them home for dinner in a more pleasant mood.

It Ain't Cheap, Folks

But why throw thousands of dollars in suspension technology at an historically utilitarian vehicle? Because pickup customers are changing; they are younger, more affluent and more than ever buying the trucks for personal use. And when they plunk down more than $50,000 on average for a pickup, they don’t want a truck that rides like granddad’s Farmall.

Despite this pickup-spending frenzy, MRC remains a costly piece of technology reserved for a $61,000 pickup such as the Sierra Denali or the equally expensive Chevy Silverado High Country.

MRC costs are not expected to come down anytime soon, either. Constant improvements to the system, such as processing speeds, will keep it exclusive. Calibrating the technology to fit different vehicle weights, and even various tire and wheel sizes, consumes valuable engineering resources, too.

If the Sierra Denali’s MRC system has a weakness, it might be at low speeds. Our seat-of-the-pants analysis suggests it works best above 35 mph (56 km/h). Any slower, the ride isn’t as agreeable.

And GM is not alone pickup-suspension tweaking. The Ram 1500 set the bar with its air suspension technology, while a recently tested Ford F-150 Limited delivered a cushy if not slightly watered-down ride. Whatever the model, ride and handling has shot up in awareness among pickup makers.

There is little to complain of elsewhere on GM’s priciest pickup. Its 6.2L EcoTec3 small-block V-8, a two-time Wards 10 Best Engines winner, grinds out a silky-smooth 420 hp even if the newly installed 8-speed transmission can get a little jumpy. A 625-mile (1,000 km) road trip in our 4-wheel-drive crew cab returned 17 mpg (13.8 L/100 km), hardly a fuel miser but not too shabby for 5,500 lbs. (2,495 kg) of Detroit iron.

Inside, the Sierra Denali gushes with the luxury of Tribeca high-rise. The driver and front-passenger seats are stylish and comfortable, while the second row ably accommodates three passengers. It offers a commando’s view of the road.

There’s lots of technology, too, such as an OnStar 4G wireless hotspot, wireless phone charging and a faster-reacting IntelliLink infotainment system with newly added Apple CarPlay and Android Auto capability.

The 8-in. (20-cm) touchscreen contains big buttons and excellent resolution, although in an interior this expansive GM should consider adding an even bigger screen soon.

Active-noise cancellation keeps unwanted noises out of the cabin.

Exterior enhancement for the ’16 Sierra Denali include high-performance LED headlamps and foglamps and taillamps, a new grille design; available 20-in. chrome-clad wheels, optional power-articulating steps and a handful of fresh colors.

IntelliBeam headlamps, which automatically switch from high-beam to low-beam depending on traffic conditions, along with automatic lane-keeping, now are included in a driver-assist safety package.

It all adds up to a high-tech, highly flexible and family-friendly truck capable of handling whatever obstacles the road might offer. Even the local highway commission here has raised the white flag and is spending $7.3 million this summer to rehabilitate that bumpy stretch. Consider it another win for the Sierra Denali.

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'16 GMC Sierra Denali Specifications