Let’s answer the question Autoweek posed here Wednesday: No, the Chevrolet Trailblazer will not ever come back to the U.S. as a reborn, full-size SUV.

Partially, it’s because Chevrolet already sells two full-size SUVs (Tahoe, Suburban), a full-size crossover (Traverse), and a smaller crossover (Equinox). Then there’s the Acadia, a GMC-only midsize SUV. But the real reason? Body-on-frame trucks, at least in the U.S., are a surefire way to kill a new model before it even has time to linger.

Just ask Kia, which introduced the body-on-frame Borrego for 2009 and gave it the sweep that same year. When my colleague Bill Griffith tested one for The Boston Globe, he wrote that the “V8 version’s ride was rough enough to be disconcerting, even after trying lower tire pressures.” Like a garbage truck.

The Nissan Pathfinder is switching to unibody construction for 2013, the once popular Ford Explorer has ditched both the V8 and truck frame, and the Lincoln Town Car -- the only body-on-frame sedan still on sale here -- is departing forever after this year.

Unibody construction makes for a more carlike experience. The body floor, pillars and roof are welded together as one unit, and the engine and suspension hang off on subframes. They are lighter and more rigid than a body-on-frame chassis, which uses two thick steel beams braced together under a separate, mounted body.

Some off-road purists say that body-on-frame vehicles, because they allow more torsion, tend to take a beating better, and they’re mostly right. That’s why every pickup truck, save for the Honda Ridgeline, and full-size van uses a body-on-frame design. Their tough, simple construction allows for superior towing, payload and overall durability in heavy-duty use. Plus, as Hemmings notes, body-on-frame vehicles are cheaper to repair after an accident -- hence the reluctance for taxi companies and police agencies to give up their Crown Vics. They’re also heavier, meaning a fuel-economy penalty is unavoidable.

But has the unibody truly decimated the body-on-frame chassis? By my count, 22 body-on-frame vehicles are on sale in the US, excluding pickups, vans and heavy-duty commercial trucks. Let’s take a quick look at why they still exist when compared with their typically better-handling, better-riding and more efficient unibody competition.

Ford Expedition/Lincoln Navigator – These hulking dinosaurs have hardly been updated since their 2000s-era heyday and aren't as popular as the GM SUVs.

Jeep Wrangler – The original American rock-crawler won’t ever change its beefy body-on-frame design. It’s the last bastion between real trucks and wannabes.

Nissan Xterra – With the Pathfinder becoming “softer,” the Xterra is a less expensive, more hard-core ride for committed SUV buyers. 

Nissan Armada – The owner of a dog-grooming business down the street from me uses an Armada to haul her 165-pound Great Dane. She needs this truck more than anyone. 

Nissan Pathfinder – The 2013 Pathfinder will share its unibody platform with the brand-new Infiniti JX. The current Pathfinder is simply old.

Infiniti QX56 – Everything is enormous and overkill on this superluxe rig. For some reason, everything that fails to gain attention in the Lincoln Navigator -- huge V8 engine, houselike proportions, is working for Infiniti.

Toyota Land Cruiser/Lexus LX 570 – The Land Cruiser and LX 570 are old classics that are almost as nice as a Range Rover for somewhat less money.

Toyota FJ – Another classic, albeit with three windshield wipers. See Jeep Wrangler.

Toyota 4Runner – See Nissan Xterra.

Lexus GX 460 – This body-on-frame SUV not only looks awkward, but handled so badly that Consumer Reports issued a “Don’t Buy” rating in 2010.

Land Rover LR4 – It’s heavy, about 5,500 pounds, and floats above the earth. But it’s also one of the most serious SUVs imaginable when the road gets rough. None of its buyers care that it gets 13 mpg in real-world driving.

Range Rover Sport – The bigger Range Rover rides on a unibody developed in tandem with BMW. The Sport rides on the LR4 chassis, yet there is nothing sporty about it; buyers, meanwhile, eat up the Sport like free-range chicken.

Chevrolet Tahoe/GMC Yukon/Cadillac Escalade – These brutes continue to sell well, thanks to their simple styling and rugged specs. The Escalade continues to be stolen very often.

Chevrolet Suburban/GMC Yukon XL/Cadillac Escalade ESV – I drove an Escalade ESV for one day in Boston and then hid the keys. If I were a bus driver, I’d have been very happy.

Lincoln Town Car – The very last rear-wheel-drive, full-size American sedan without a unibody chassis. Livery drivers are seriously worried that no other car will replace the Town Car's smooth-riding, long-lasting performance for the money.

Mercedes-Benz G-Class – The Cold War relic that keeps on giving. Built on the same chassis since 1979, this German troop transport defies any and all logic, especially when the sticker gets to $130,000. 

Absolutely none of these vehicles returns decent fuel economy. Many, like the Infiniti and Rovers, are ultrapricey. Others, like the Wrangler and FJ, are in unbeatable niches. Most, if not all, make no sense to European citizens crushed under $8-per-gallon gasoline.

So while it’s tough, if perhaps even impossible, to launch a completely new body-on-frame truck, it’s apparently quite simple to keep the gas-guzzling brutes we have. What red-blooded, truck-loving Texan would disagree?

Clifford Atiyeh has spent his entire life driving and riding in cars he doesn't own. He was raised in Volvos and has grown to love fast, irresponsible vehicles of all kinds. He lives in Boston, is a member of the New England Motor Press Association, and has reported for The Boston Globe, Car and Driver, Popular Mechanics and The Times of London.