In four-wheel-drive form, the 2014 Chevrolet Silverado 1500 stands 74 inches tall, but in the eyes of General Motors, this truck is nothing short of a giant. Saying trucks are the lynchpin of the General's fortunes in North America is no understatement. Full-size trucks -- especially pickups -- are essential to GM's bottom line. Chevrolet sold 418,312 Silverado pickups in the U.S. last year, making it the most popular model in the division's North American portfolio and the most popular GM nameplate. Despite the Silverado's significance, GM hasn't exactly kept abreast of updating its light-duty bread-and-butter pickups. Thanks to an economic shakeup, a slow housing market, and the pesky matter of a corporate fiscal meltdown and restructuring, the 2014 Silverado is GM's first attempt at significantly overhauling its full-size truck portfolio. We had our first look at the new Silverado last November, but now that the first examples are starting to trickle to dealers, we had a chance to slide behind the wheel to see what's new.

NIP/TUCKED, BOTH INSIDE AND OUT

Drive past a new 2014 Silverado on the expressway and you might mistake it for its predecessor, but park the two trucks side by side and there's little room for mistaken identity. Yes, the split grille, quad headlamps, massive bow-tie emblem, and boxy form carry through to the new model, but according to design chief Tom Peters, these are all signature Silverado cues that the new truck needed to keep. The new truck does have those familiar styling elements, but overall it's a little brawnier and more brash than the previous model. The blistered hood gives way to a massive grille opening that's about as tall as those used in heavy-duty Silverados. The grille surround carries into the stacked headlamps, which boast projector low-beam lighting on higher trim models. Fenders and wheel arches are still rather square but look more muscular than before. The visual effect is accentuated by the new Silverado's wider track and stronger shoulder line. Everything aft of the A-pillars almost looks carried over, but that's not the case. All cabs -- be it regular, double, or crew -- are completely new for 2014. The windshield is a degree flatter to improve aerodynamics, and the doors no longer wrap around the upper edges of the cab. Instead, they're now inset into the cab sides and are triple sealed to cut wind noise. Double cabs ditch the old suicide half-doors for fixed B-pillars and forward-hinged doors, and crew cabs have longer rear doors and a couple extra inches of rear-seat legroom. GM also added reinforcement to the cab and increased the use of high-strength steel while adding enlarged hydraulic body mounts. The result? A stiffer, more isolated cab. The fully boxed frame, for the record, isn't much different from the last truck. It still boasts a hydroformed front section, but additional high-strength steel in the middle section allowed GM to increase stiffness and shave 44 pounds. The front suspension remains an independent, coil-over-shock arrangement, but control arms are now made from forged and cast aluminum instead of steel, and anti-roll bars are thicker than before. Leaf springs are retained out back but are a little lighter and wider than in prior Silverados.

TEACHING AN AGING POWERTRAIN NEW TRICKS

At first glance, the 2014 Silverado's engine lineup seems old hat. The 4.3-liter V-6, 5.3-liter V-8, and 6.2-liter V-8 have been staples seemingly forever -- but the entire range, now sold under the EcoTec3 moniker, has been significantly updated. All three engines use aluminum blocks and heads, direct fuel injection, 11:1 compression, and cylinder deactivation. The latter isn't an all-new function, but Chevrolet has added a few tricks -- notably some NVH concessions in the exhaust system -- that allow the engines to run on four cylinders for longer periods of time. All three powerplants also eschew hydraulic power-steering pumps in favor of electric power-steering racks. Predictably, adding direct fuel injection and increasing compression yields more power. The 4.3-liter V-6 is the best example. While the ancient, outgoing 4.3-liter wheezed along with 195 hp and 260 lb-ft of torque, the new 4.3-liter serves up 285 hp and 305 lb-ft of torque. Horsepower-wise, that's not quite enough to trump the base six-cylinder offerings from Ford and Ram, but the Silverado's base six does have the most torque in the segment. Spec a crew-cab Silverado just right, and a 4.3-liter truck can tow up to 7200 pounds. The 5.3-liter V-8's output also increases compared with its predecessor, but not by as much as the V-6. For 2014, the direct-injection V-8 serves up 355 hp at 5600 rpm and 383 lb-ft of torque at 4100 rpm. Early estimates from GM suggest two-wheel-drive Silverados with this engine could be rated at 16/23 mpg (city/highway), while four-wheel-drive models could attain a 16/22 rating. Figures for the optional 6.2-liter V-8 have yet to be formally announced, but Jeff Luke, chief engineer of the Silverado program, says his team is targeting output in the neighborhood of 400 to 450 hp. We expect the official numbers to emerge shortly before the engine goes on sale this fall. Even with three engine options, the 2014 Silverado has but one transmission to choose from: a six-speed automatic. The 6T80E is essentially unchanged from 2013, despite the fact that some competitors are rolling out eight-speed automatics. Luke says the new Silverado would show even bigger fuel-economy gains with additional gear ratios but says we'll have to "stay tuned" for some "neat things planned for the next few years." GM officials shy away from talking about its eight- and ten-speed automatic transmission programs, but we wouldn't be surprised if development timetables for either transmission didn't line up with that of the new Silverado.