Heavy Reign: 2011 Chevrolet Silverado/GMC Sierra HD First Look
Things don't usually happen this quickly in the truck world. The typical product cycle time for a pickup is about seven years, yet in the case of the Silverado/Sierra HD, the time between new models has been pretty short--about four years--motivated by tough new emissions standards. And with the push on to make a diesel-powered truck meet the new federal requirements, the engineers took the opportunity to upgrade the rest of the truck while they were at it.
You can see from the photos that the new generation of Silverado/Sierra HD hasn't changed that much visually. In fact, you can count the number of major differences in styling between the 2010 and 2011 on one hand: a louvered hood, new front bumper and grille, and, for the first time, 20-inch wheels. But don't be fooled by the near-carryover body--when the economy went south, budgets were cut and things quickly changed at GM. The guys working on this project had to prioritize, and spent more resources on improving the function of the truck than updating the styling (see sidebar). So instead of looking at all-new sheetmetal, the result is a truck that's much more capable than ever before, with more power and dramatically lower emissions. Your neighbor might not know this is an all-new pickup, but you certainly will.
The Silverado/Sierra HD is powered by a choice of two engines: a gas 6.0-liter Vortec V-8 or a 6.6-liter Duramax turbodiesel V-8. As of press time, SAE testing hasn't been completed on either engine, so horsepower and torque numbers aren't yet available--but we expect both to be higher on both V-8s. The Vortec is backed by a Hydra-Matic 6L90 six-speed automatic; the Duramax uses an Allison 1000 six-speed auto. The 6.0-liter receives a new camshaft profile, said to help the engine produce more torque lower in the powerband. The big news, though, is with the diesel.
The regulations call for nitrogen oxide (NOx) emissions to be reduced by 90 percent, and to achieve that, GM had to make significant changes to the Duramax. The company was able to use some carryover components of the 6.6-liter, but about 60 percent of the parts are new. GM's approach is similar to the one Ford took with the 2011 Super Duty's diesel--to comply with the new regulations, the Duramax now uses an updated exhaust gas recirculation system (which reduces the amount of NOx produced during combustion) and a selective catalytic reduction aftertreatment system. With SCR, a small amount of urea-based diesel exhaust fluid is sprayed into the engine's exhaust gases. When the fluid mixes with the hot gases, the urea is converted into ammonia. The ammonia and a catalyst convert the NOx into emissions-friendly nitrogen gas and water vapor. The more demand put on the engine, the more DEF is used. The system also uses a diesel particulate filter to trap soot, and the filter regenerates about every 700 miles.
Expected range between DEF refills is about 5000 miles. When the DEF tank starts running low (there will be warnings), speed is limited to 55 mph, and when the tank is empty, you won't be stranded--but the truck won't go any faster than five mph.
Also included as standard equipment with all Duramax diesels is an exhaust brake. While pricing hasn't yet been announced, we anticipate the new emission-control systems will add a slight premium to the cost of the diesel engine. Fuel efficiency is also said to be higher than with the previous generation's engines; that, plus the larger fuel tank (now 36 gallons as opposed to 34), means the truck's range is as high as 680 miles on a single tank of fuel. The EPA doesn't rate trucks this heavy, but that range and tank size suggest this Chevy should achieve about 19 mpg on the highway.
Dimensions are increased slightly: Wheelbases are up about 0.6 inch compared with the 2010 models, overall length has grown about 0.3 inch across the line, width remains the same, and height varies depending on model, but is within an inch or so of the previous truck. The track is wider: up by 0.2 inch in front, 1.3 inches in the rear. More high-strength steel is used, and the frames are fully boxed; bending stiffness has increased 92 percent, beaming stiffness is up 20 percent, and the front frame structure is 125 percent stiffer. GM also reduced vibration in the truck with the use of larger engine and transmission mounts, and hydraulic body mounts are included on extended- and crew-cab models. These new underpinnings are also said to improve ride and handling.
Body styles continue as regular cab, extended cab, or crew cab, and all (except the longbed-only regular cab) are also offered with a choice of short- or longbed. The rear doors on extended cabs now open 170 degrees for easier access. Bed dimensions stay the same (6.6 or 8.1 feet long). Inside, headroom is about 0.1 inch lower and legroom and shoulder room are identical to those of the 2010 model. Cabin features include mobile WiFi, Bluetooth, navigation, and XM Satellite Radio with NavTraffic. A new option is the GMC Sierra Denali HD (all images of the GMC in this story are of the Denali); this is the first time GMC has offered a Denali version of a heavy-duty truck. The Denali package, available only on the 2500, comes as a 4WD crew cab short bed, with the Vortec engine standard and the Duramax optional. While the regular Sierra HDs come with a three-bar grille, the Denali has a four-bar chrome grille, and also comes with body-color bumpers, 18- or 20-inch chrome wheels, and chrome accents.
The redesigned torsion-bar front suspension now allows for a 25-percent-greater Gross Axle Weight Rating up front--as high as 6000 pounds. It uses stronger, lighter forged steel upper control arms and cast-iron lower control arms, with five different torsion-bar rates for the truck's five front GAWRs. Rear suspension uses wider leaf springs--two-stage with 2500s, three-stage with 3500s--now asymmetrical to reduce axle hop, and the larger size increases rear GAWR to a maximum of 9375 pounds on duallys. It isn't just the GAWR that has increased, either: Towing capacity is now 16,000 pounds with a ball hitch, 20,000 with a fifth-wheel; and maximum payload is 6335 pounds.
Brakes are larger on the new model: disc diameter is 14 inches front and 14.2 rear--an increase of 1.2 inches. The rotors are also wider, and the calipers are stiffer and stronger. Four-channel ABS is standard with single-rear-wheel models, as are StabiliTrak, hill start assist, and trailer-sway control; a three-channel system comes with duallys. Side and side-curtain airbags are optional.
The HDs will go on sale late spring. They'll be built in two plants. The regular cabs and crew cabs will be built in Flint, Michigan, and production of the extended cabs will start in Fort Wayne, Indiana, about a month and a half later. When it comes to towing and payload capacity, the Silverado's numbers are impressive and surpass those of the Ram HD's, and in some cases those of the Super Duty (see sidebar). We can't wait until we get our hands on all three of these new heavy-duty trucks at the same time, to see which one is king of the hardest-working truck segment out there.
|How the Regular Cab 4WD Duallys Stack Up|
|Vehicles||Max Payload||Max Towing-- conv||Max Towing-- 5th wheel||Max Fuel Cap||GVWR||GCWR||Brakes, F/R
||2011 Chevy Silverado HD 3500 Longbed|| 6308 lb||16,000 lb||20,000 lb||36 gal||13,000 lb ||26,000 lb||14.0/14.0 in
||2011 Ford F-350 Super Duty
Longbed|| 6520 lb||14,000 lb||21,600 lb||40 gal||13,050 lb||29,000 lb||13.7/13.4 in
||2010 RamHD 3500
Longbed|| 5130 lb||16,000 lb||17,300 lb||35 gal||12,200 lb ||24,500 lb||14.2/14.1 in
The Man in Charge
Rick Spina: GM's Global Leader for Full-Size Trucks
Rick Spina: GM's Global Leader for Full-Size Trucks
With almost 20 years of experience with the GM truck group, Rick Spina, the new global vehicle line executive for full-size trucks, knows birthing a new heavy-duty pickup is no easy task. "We've got a chance with this new truck to do something special, and give our customers more of what they like," he says. Of course, that doesn't come without significant challenges, especially with so much riding on every decision. "We know we're being watched pretty closely and everyone wants to see how we're spending our money...but the truth is the loan from the government has forced us to scrutinize every single dollar. We have to make sure every change will give our customers what they want." We're guessing that's why the new Silverado HD and Sierra HD work trucks won't have a lot of interior or exterior styling changes. "We put all of our efforts, all of our resources into making the platform of this truck better, stronger, stiffer in every way. We had to ask ourselves at every stage--where can we give our truck guy the biggest bang for his buck?" Rick describes his team's process as if he was part of a remodeling crew, improving the foundation and beam supports to a house.
Sure, all the bracing and supports in the basement may not be the sexiest part of the house, but when the bad weather hits, you'll be glad you had it done. And from the looks of it, the same strategy could work pretty well with the new Chevy and GMC HD trucks. At least that's what Rick Spina is hoping for. He finishes our interview by saying, "Most of our truck guys know all the real sexy stuff is under the skin anyway."--Mark Williams