The 2021 Chevrolet Tahoe and Suburban are the biggest things to happen to the bow-tie brand this year. No, really, this isn't entirely a stupid pun about the SUVs' considerable size. While the Car Folk at General Motors, like Mary Barra, Mark Reuss and of course engineer Tadge Juechter are most proud of their prodigal halo, the Corvette, we'd guess it would take hundreds, if not thousands of $60,000 Vette sales to equal the profit margin on one of these full-size sport/utility vehicles. These Chevys pay for indulgences as the next Z06's flat plane-crank engine as much as they keep the lights on at the company's Renaissance Center in Detroit.

Chevrolet once boasted it sold more vehicles with a manufacturer's suggested retail price of more than $35,000 than any other company, and that was maybe 15 years ago. Some three Tahoe/Suburban generations later, a 2021 Chevy Tahoe or Suburban with the High Country trim level, if not the next-tier Premium, will easily set you back as much as a Corvette Z51—that is, more than $70,000.

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The all-new Tahoeburban twins are once again based on the Silverado's pickup-truck platform, albeit this time with a breakthrough: A fully independent rear suspension. This not only differentiates the Tahoe and longer-wheelbase Suburban from the Silverado 1500, which continues to use a leaf-sprung solid rear axle, it also aligns the Chevys with their cross-town rivals, the Ford Expedition and Ford Expedition Max. The new rear end should deliver better on-road suspension refinement than before, all the more so given how an air springs and electronically adjustable dampers will be available as options. Otherwise, the T1 body-on-frame sport/utility pretty much shares its chassis with the pickup truck, says Matt Noone, Chevrolet trucks design director.

The long-awaited upgrades arrive a full decade since Chevrolet introduced the now-previous-generation Tahoe and Suburban models, and are joined by functional improvements, as well. Unlike their predecessors, both rigs trade their bulky removable third-row seats for modern flat-folding setups (which join flat-folding second-row chairs). Like the independent rear suspension, these features finally match up with the competition. The Fords, as well as their Cadillac Escalade-fighting Lincoln Navigator siblings, already are on their second-generation platforms with independent rears and flat-folding third rows.

Chevy says the new seating package boosts cargo space behind the Tahoe's third row by 66 percent, and third-row legroom swells by 10 inches. Behind the bigger Suburban's third row, cargo space is up more than 19 percent (and maximum space with the seats folded is now a whopping 144.7 cubic feet!). In addition, the second row of the Tahoe and Suburban have 10-inches of seat adjustment travel. And the load-floor heights for both models are between four and five inches lower than the outgoing solid-axle models'.

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The Tahoeburbanites are bigger than before, and both models are longer and about an inch taller than their predecessors with beltlines that are about one inch lower, enlarging the windows somewhat. Both the Tahoe and Suburban each sit on longer wheelbases, with the former's growing by roughly five inches and the latter's nudging up by about 1.5 inches. On the Tahoe, the rear wheel openings no longer intrude on the door apertures, improving entry to the rear.

Engine options for the Tahoe and Suburban, as you probably expected, come straight out of the Silverado catalog. That means a 355-hp 5.3-liter V-8 with Dynamic Fuel Management (fuel-saving cylinder deactivation) and stop-start and a 420-hp 6.2-liter V-8 (also with Dynamic Fuel Management and stop-start). A diesel engine option makes its return to the Suburban family for the first time in years (and is available on the Tahoe). It is the Silverado's new 277-hp 3.0-liter turbo-diesel inline-six, which matches the 6.2-liter's 460-lb-ft peak torque figure.

Stylistically, the Tahoe and Suburban wear the same, um, expressive face as the new-for-2019 Chevy Silverado. Designers also stamped in more distinctive bodyside surfacing than they did on the Silverado, which lend the trucks a subtle coke-bottle midsection pinch. Distinct grille meshes  and standard 22-inch wheels differentiate the High Country and Premier trims from the mainstream LT and LS models. There also is a sporty RST package for both Tahoe and Suburban models, and a Z71 off-road package returns but for the Tahoe only. This time, the Z71 package is a more serious off-roader, with a raised, tapered lower front fascia that affords better clearance over obstacles (and improved off-road approach angles). The Z71's air suspension can be raised or lowered by up to four inches, including a higher height for off-roading and lower height for highway speeds and easier ingress/egress.

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The interiors of both trucks are massively improved. There's virtually no relation between them and the current Silverado's lackluster innards, which have been universally panned since that truck arrived for 2019. There are real woods and metals in the SUVs' cabins, a 10.0-inch center infotainment screen, a new 8.0-inch digital gauge cluster, and a huge 15.0-inch head-up display. There are even 12.6-inch screens on the backs of the front-seat headrests to dazzle second- and third-row passengers. A panoramic sunroof is standard on upper trims, while the High Country boasts bronze metallic accents and an overall elegance not found in Chevy's equivalent full-size pickup.

Within a year, GMC-badged versions of these Chevys will arrive, along with a Ram pickup-based Jeep Wagoneer lineup. That means the full-size trucky SUV octagon will grow plenty crowded. But if you have questions about the Chevy Tahoe/Suburban's chances of success in the face of all this competition, consider that Ford Expedition/Expedition Max sales rose 5.4 percent in 2018, to 54,661 units. During the same period, the ancient previous Tahoe and Suburban were upsixpercent, to 164,786. That's a lot of fun Corvette-funding development cash.

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