When one of your best sellers is up for a redesign, you best be careful with the direction you next point that franchise player. And when the model also happens to be longest running nameplate in the industry, as is the case with the Chevrolet Suburban, you dare not make a misstep.

To that end, the 2015 Suburban has been reimagined as a more contemporary truck that the General hopes will continue to be attractive to the base, while also pulling new customers into the fold. Come to think of it, that sounds like it has the makings of a good political strategy, too.

Join us as we put the redesigned ‘burban, along with its shorter Tahoe relative, to the test on a road trip from the ski resort community of Lake Tahoe to the vine-covered region of Napa, California.

From the ground up.

Though it continues to use a traditional body-on-frame configuration, the 2015 Suburban is new from the ground up. Now in its 80^th year and 12^th generation, this SUV is the latest version of what started as a wagon to haul cargo and parcels for businesses and estates. Today’s behemoth has practically grown to the size of a rolling house, but it has people and cargo carrying capability to match.

The Suburban measures in with a 130-inch wheelbase and 224 inches of overall length. Buyers not needing the extra cargo space behind the third-row seating can opt for the Tahoe, which is less lengthy by 20 inches. Both are motivated by a 5.3-liter EcoTec3 V8 – familiar from GM’s latest pickups – that provides 355 horsepower at 5,600 rpm and 383 lb-ft of torque at 4,100 rpm. Switch from gasoline to E85 in this flex-fuel engine and GM says output will increase to 380 horsepower and 416 lb-ft of torque.

Equipped with an active fuel management system, the 5.3-liter can shut down four of its eight cylinders once it reaches cruising speed. With the increase in power from the outgoing motor, GM engineers claim the engine can remain in efficient four-cylinder mode for longer periods. In conjunction with direct injection, variable valve timing and a standard six-speed automatic, this technology helps the Suburban to achieve an EPA-estimated 16/23 city/highway mpg with RWD and 15/22 with 4WD.

Towing capacity for the RWD version is 8,300-pounds, while our 4WD tester gets downgraded just a hair to 8,000-pounds. An available Max Trailering package adds a trailer brake controller and two-speed transfer case. Also along for the ride: GM’s Magnetic Ride Control, which monitors the road for on-the-fly shock absorber adaptability to changing conditions, just as a similar system does in the Corvette Z06 and Cadillac CTS-V.

Stylistically, the Suburban and Tahoe have struck out on their own, not sharing a single piece of sheetmetal with the latest Silverado 1500. Featuring crisp new panels with creases for added emphasis, they appear boxier than before, but not in a bad way. They have, however, borrowed some of their pickup relative’s tricks, including the use of inlaid doors that cheat the wind ever-so-slightly for improved interior quietness. Lightweight aluminum hoods are another commonality, although the SUVs also get aluminum liftgates in their automotive version of a battle of the bulge.

Interior decorating.

The Suburban is a five-door, three-row vehicle that can haul from six- to nine passengers, depending on configuration. Available in base LS, LT and range-topping LTZ versions, it is now standard with second- and power-folding third-row folding seats, and an above-floor cargo bin that is removable via the twist of a couple of thumbscrews. Through the use of the above-floor bin, the rear cargo area provides a fully flat loading floor.

As in most of the premium offerings from General Motors, our Suburban LTZ was equipped with heated and ventilated leather seating surfaces, and included a haptic driver’s seat function to vibrate “alerts” when crossing over a lane marking on either side of the vehicle. It was also fitted with a front seat center airbag to mitigate any injuries to the person on the opposite side of the impact zone. Adjustable pedals customize the fit for virtually every driver.

On the infotainment front, there’s an eight-inch display and next-generation MyLink connectivity for audio, Bluetooth, navigation and 4G LTE Wi-Fi connections that will appear later this year. A rear-seat DVD entertainment system is available with dual fold-down screens. There are six USB ports and six power outlets, including a three-pronged 110-volt plug to power everything from gaming consoles and laptop computers to George Foreman grills.

The Suburban can carry more than just people. Rear cargo space checks in with 39.3 cubic feet behind the third row seat. Push the power fold button and it grows to nearly 77-cubic feet of space behind the middle row. Fold both of those, and the Suburban becomes a 121-cubic foot, flat-floor hauler. For the record though, it’s around 16 cubic feet short of what the outgoing model provided.

On the downside of interior refinement, we were disappointed to find Chevrolet’s traditional (and poorly executed) version of faux wood trim throughout the Suburban. At this price point, Chevy’s interior designers should be woodshedded into using the real thing. After all, the Suburban’s MSRP can climb above $70k with options.

In a nod to a burgeoning, uh, secondary market – GM’s big SUVs are among the most frequent stolen vehicles in the U.S. – the automaker has added an upgraded optional anti-theft system with sensors that recognize glass breakage, vertical movement (jacking the vehicle to remove wheels and tires) and interior movement. In the event of any of these felonious activities, the Suburban’s alarms will sound and the key systems become disabled.

Cross-country.

The 2015 Suburban exhibited plenty of power from the 5.3-liter V8, which surprisingly gave a nice kick back into the well-bolstered front row seating. Power delivery was seamless, and most of the time during our highway stints, we were unaware that we were operating in four-cylinder mode. It was only after a glance downward on the driver’s IP that we noticed a V4 symbol amongst the gauges.

Interior quietness is top shelf by way of the added emphasis on NVH mitigation. Through the use of wind-cheating designs and laminations, we never had to raise voices, even during conversations with second and third row passengers. To our ears, the only sound that gets into the interior is the throaty growl of the exhaust.

With the 2015 Suburban all new from the ground up, GM could utilize its trickest kit possible in the top-of-the-line LTZ. The ride and handling benefitted from an improved structure, the Magnetic Ride Control, a five-point multi-link rear suspension and new tires tuned specifically for the vehicle. The electric power assist steering setup provided good feedback from the road and offered quick response for rapid lane changes as needed. Though top-heavy by its nature, the Suburban did not transmit excessive side-to-side wallow. The net result was a vehicle that tracked smaller than it actually is. With its proven solid rear axle, GM feels it still gives the best combination of ride, handling and towing capacity.

Leftlane’s bottom line:

Chevrolet’s glimmer twins get a total transformation that keeps them moving forward with modern design and amenities. During our cross-state adventure, we found the Suburban capable of everything we asked of it; we’re sure that buyers will be similarly satisfied.

2015 Chevrolet Suburban LTZ 4WD base price, $64,700. As tested, $73,625. (Base LS 2WD, $45,595.)

“Sun-Entertainment-Destination” package, $3,305; Power running boards, $1,745; Adaptive cruise control, $1,695; Max trailering package, $500; Crystal red metallic paint, $495; Theft deterrent system, $395; Cocoa/Mahogany interior, $295; Destination charge, $995; Package discount, -$500.

Photos by Mark Elias.