Vehicle Overview Redesigned for 2007, the GMC Sierra full-size pickup has been restyled, inside and out, and boasts roomier cabins, greater maximum towing capacity and higher gas mileage. GMC says ride, handling and interior noise levels are also improved.
The light-duty 1500 series goes on sale late in 2006, and the heavy-duty (2500 and higher) versions follow in early 2007. Its late arrival means there are actually two different vehicles that have the 2007 designation: the new generation detailed here, and the previous generation that now has the Classic name added to it. (Skip to details on the: 2500HD, 3500, GMC Sierra Classic)
Despite a concerted effort by General Motors to differentiate the Sierra more than ever from the Chevrolet Silverado, its sister model, they succeed only to a point.
As before, the Sierra shares a platform with the Yukon and Yukon XL full-size SUVs. These models came first on this all-new platform, making their 2007-model debut earlier in 2006. The varieties are overwhelming: regular, extended and Crew Cab body styles; short, standard and long cargo box lengths; multiple powertrain combinations; five suspension packages; and four trim levels. Of course there's also rear- or four-wheel drive.
Exterior Like the new Silverado, the Sierra's exterior styling has changed. It's different and modernized, and though it has different hood and fender shapes, it still isn't wildly different from the Silverado. Its headlights are stacked vertically, like the Silverado's, but the Sierra's are more squat. A taller bumper rests immediately under them. Where the Silverado's disproportionately large grille is chrome-heavy, it's dark and only rimmed with chrome in most of the Sierra trims. The Denali model retains its signature perforated chrome plate grille.
On both models, the windshield is more swept back, yet the nose is taller and more squared off. The end result is better aerodynamics, which plays a part in the improved fuel economy.
The official trim levels are WT (work truck), SLE1, SLE2, SLT and Denali, the wheels of which range from 17 to 20 inches in diameter. The Denali's standard 18s and optional 20s are unique to the trim level.
The cargo bed lengths are 5 feet 8 inches, 6 feet 6 inches and 8 feet. Not all lengths are available with all cab styles and powertrains, though.
Interior The new Sierra generation has markedly improved interior quality, with less-plasticky plastics and lower shine. The WT and SLE trim levels have an interior design all their own, with a different dashboard and larger controls and handles (for easier operation with gloved hands, GMC says). Storage capacity has grown thanks to a double glove compartment and even-larger center storage consoles. The SLE1 has a 40/20/40-split front seat. Not really a bench, this configuration is like two bucket seats with a small seat between them that converts into a center armrest/console. It has a lockable bin in the center seat and another in its backrest/armrest. Leather is optional on the SLE trims, with a six-way power driver's seat added in the SLE2.
The higher trim levels get a different interior layout borrowed from the Yukon SUV, intended more for personal pickup users than for workers. In addition to the different dashboard, door panels and trim, the SLT adds heated leather seats with 12-way power adjustment for the driver, a six-CD changer with Bose speakers and heated windshield washers.
The Denali has exclusive leather and trim and a unique steering wheel and center console, as well as power adjustment for the passenger seat. Adjustable pedals, an auto-dimming rearview mirror, dual-zone climate control, remote starting, rain-sensing wipers and sonar rear parking assist are some of the Denali's standard equipment.
In addition to added front-seat legroom, headroom and hip room, GMC made the interiors seem roomier by moving the dashboards down and forward a few inches. GMC says the rear seats are more supportive and offer more legroom in both extended and Crew Cabs. The crews have split rear seats that raise to provide more storage space. They're optional in extended cabs, which now have Nissan Titan-style access doors, which open 170 degrees. They also have power windows in the higher trim levels.
Under the Hood There are still 4.3-liter V-6 and 4.8-, 5.3- and 6.0-liter V-8 engines paired with a four-speed automatic transmission, but the big news is that the Denali now gets a 6.2-liter V-8 mated to a six-speed automatic — a combination available elsewhere only on the Cadillac Escalade. It generates 400 horsepower; the 6.0-liter tops out at 367 hp. The transmission includes a sequential manual mode that lets the driver shift up and down by means of a switch on the column shifter.
The 5.3-liter engine includes fuel-saving cylinder-deactivation technology and is flex-fuel — capable of running on E85 ethanol and/or gasoline. The 6.0- and 6.2-liter engines grant the maximum capacities of 10,500-pound trailer weight and 2,160-pound payload.
This capability also requires one of five suspension choices, called NHT. The other four Z-based suspension names (like Z71) are for a smooth ride, enhanced (but not maximum) trailer towing and handling, offroad capability and street performance.
GMC has moved toward more-refined systems that have been finding their way into SUVs and other trucks: Coil springs have replaced torsion bars in the front suspension, and the recirculating-ball steering has given way to the lighter, simpler and more precise rack-and-pinion design. The Denali has skid plates and tow hooks as standard equipment.
Safety Antilock brakes are standard on all models. The StabiliTrak electronic stability system is standard on Crew Cabs and optional on extended cabs but not available on regular cabs. In addition to the required airbag complement, side curtain airbags are optional for all three body styles. They deploy along all the side windows in the event of a side impact or a rollover. GMC says the front seat belt pretensioners are designed to cinch the belts in both front and rear collisions in an attempt to prevent occupants from flopping around and being injured.
The Sierra comes with OnStar, with the first year of Safe & Sound service free. This plan includes automatic OnStar notification in the event of a collision, stolen vehicle tracking and remote door unlocking should you lock your keys in the car.
2500HD The new trucks get new engines as well. The standard engine is a 6.0-liter V-8 that produces 312 hp and 373 pounds-feet of torque. A 6.6-liter turbo-diesel is optional; it makes 365 hp and 660 pounds-feet of torque. Both engines are mated to a six-speed automatic transmission.
The trucks are offered in regular, extended and crew cab configurations, with two cargo box lengths. GM says it has redesigned the tailgate to lessen its mass and make it easier to use and remove.
Both the interior and exterior have been redesigned to make HD versions look different from their milder cousins. Differences include larger door-pull handles, plus a new grille, hood and front fenders.Back to top
3500 GMC's new 3500 trucks also get new engines. Standard is a 6.0-liter V-8 that produces 312 hp and 373 pounds-feet of torque. A 6.6-liter turbo-diesel is optional; it makes 365 hp and 660 pounds-feet of torque. Both engines are mated to a six-speed automatic transmission.
Dual rear wheels and an 8-foot cargo box are available on 3500 models. The trucks are offered in regular, extended and crew cab configurations, with two cargo box lengths. GM says it has redesigned the tailgate to lessen its mass and make it easier to use and remove.
Both the interior and exterior have been redesigned to make HD trucks look different from their milder cousins. Differences include larger door-pull handles, plus a new grille, hood and front fenders. Back to top
GMC Sierra Classic While a redesigned Sierra pickup truck is in showrooms as an all-new 2007 model, the old Sierra lives on as the 2007 Sierra Classic.
Sierra Classics are available in half-ton 1500, three-quarter-ton 2500HD and one-ton 3500 forms. No regular 2500 series exists, but a 1500HD is offered. Whereas the higher-rated models provide an increased level of hauling and towing capabilities, the 1500 series offers editions that aren't available in the others, like the Sierra Denali luxury pickup. GMC also offers a Sierra Hybrid. Though its electrical motor does not actually propel the vehicle, GMC still classifies it as a hybrid.
Regular cab models seat either three occupants on a bench or two in twin buckets, while extended cab pickups have a rear bench seat and can carry five or six people. Models with bucket seats have a standard center console that flows up into the instrument panel. Optional uplevel mirrors have a power-folding feature for parking in narrow spaces. Available camper mirrors offer manually extendable surfaces for increased visibility when towing a camper or trailer.
The engine choices for the Sierra 1500 include one V-6 and a selection of V-8s. A 195-hp, 4.3-liter V-6; a 285-hp, 4.8-liter V-8; and a 295-hp, 5.3-liter V-8 are offered. A version of the 5.3-liter V-8 can run on gasoline or E85, which is 85 percent ethanol and 15 percent gasoline. An aluminum variant of the 5.3-liter V-8 produces 310 hp. The Denali is fitted with a 345-hp, 6.0-liter V-8, while the 1500HD is powered by a 300-hp, 6.0-liter V-8. Available transmissions include a five-speed manual and a four-speed automatic.
Daytime running lights and antilock brakes are standard. GM's OnStar communication system is available on some models. Back to top