Don’t be surprised if you see more under-the-skin advertising visuals of General Motors’ new 2011 Chevrolet Silverado and GMC Sierra 2500HD and 3500HD pickups than pictures of just sheet metal.
Since more capability, via chassis and powertrain engineering, is the big story for 2011, ads will focus on the trucks’ pluses, minus the bodies. New Silverado and Sierra HDs offer increased power, and upgraded towing and payload capacity — key ingredients in the formula grabbing the attention of serious truckers.
The frame is constructed from fully boxed assemblies, and there are more cross sections, greater use of high-strength steel and more-rugged hydroformed front sections. Along with the beefier frame are larger engine and transmission mounts, and — on extended and crew cab models — hydraulic body mounts are fitted under the cab.
Teaming with the upgraded chassis are improved suspension systems, adding strength and capability at the front and rear. Up front is a new-design independent suspension system, which rated at a 6,000-pound capacity has a 25 percent greater front gross axle rating than its predecessor. GM engineers boast that 4WD models with a special prep package can — for the first time — accommodate a snowplow.
The rear gains load capacity with larger leaf springs, which at 3 inches wide are 20 percent wider than the previous model’s.
Axle hop is reduced and traction control efficiency enhanced via an asymmetrical design with unequal front and rear spring half-lengths.
The more-substantial frames and stronger suspensions contribute to a tow rating of up to 17,000 pounds with a conventional ball hitch and up to 21,000 pounds with a fifth-wheel hitch. Maximum payload is 6,635 pounds. Along with improved workhorse capability, the 2011 Silverado and Sierra heavy-duty pickups offer excellent handling and ride quality for big trucks.
A huge chapter in the under-the-skin story is a new version of the Duramax 6.6-liter turbodiesel, which delivers more horsepower and torque, and improved fuel efficiency and emissions.
Output is 397 horsepower at 3,000 rpm and 765 lb.-ft. of torque at 1,600 rpm. The special transmission used to handle this massive torque is a strengthened Allison 1000 six-speed automatic. It’s estimated that with the 36-gallon tank full the pickup can cruise on the highway up to 680 miles.
Returning for the 2011 model year is the Vortec 6.0-liter V-8 gas engine. It pairs with a strengthened version of the Hydra-Matic 6L90 six-speed automatic transmission. The 6.0-liter moves the pickups with 360 horsepower at 5,400 rpm and 380 lb.-ft. of torque at 4,200 rpm.
Bringing the powerful Silverado HD and Sierra HD to a stop is a more-efficient process with larger brakes.
Rotors, front and rear, have grown to 14 inches and calipers are beefier. Noticeable is a solid pedal feel and low braking effort.
Testing the trucks on steep mountain roads provided repeated opportunities to use the driver-selectable exhaust brake system, which is standard on the Duramax. An advantage of this “smart” exhaust brake system is that it works in sync with the cruise control. Other available features contributing to enhanced control are trailer sway control, integrated trailer brake control, hill start assist, automatic grade braking and intelligent brake assist.
Convenience can be added with technologies such as a rear backup camera, UBS connectivity, Bluetooth connectivity, XM Satellite Radio, OnStar 9.0, navigation and mobile WiFi. The Denali is an uplevel-appointed model, which has been offered in other GMC models, available for the first time on Sierra 2500HD and 3500HD series crew cabs.
GM’s focus in creating its 2011 Heavy Duty pickup was on capability — not cosmetics. Interior design basically is the same as previous models, albeit quieter and more comfortable via the chassis upgrades. Exterior changes are minimal. Both Silverado and Sierra sport a macho power-dome hood with a new louvered design, fresh-look grille and a full-width chrome steel front bumper.
For 2011, both the Silverado and Sierra heavy-duty lineups expand. Silverado 2500HD is available in 10 models and eight single- and dual-rear-wheel 3500HDs. The Sierra heavy-duty lineup includes a dozen 2500HD models and nine single- and dual-rear-wheel 3500HDs.
Pricing for Silverado and Sierra heavy-duty pickups starts at $27,965, plus $995 destination charge for a 2500 regular cab 2WD model. Upgrading to the Duramax diesel and Allison transmission combo adds $8,395 to the price. — Tim Spell, Motor Matters
(Tim Spell is automotive editor for the Houston Chronicle InMotion section.)
Copyright, Motor Matters, 2010