The 2007 Dually now has one-piece bed sides that give a smooth, sculpted look to the new model. Also note the cab running lights are more stylish than those found on the previous model.
GM’s Heavy Duty pickups — new bodies, more power, same bones
“These old bones ain’t what they used to be.”
Those words keep flitting around in my head as I glide past slower traffic while powering up a long, steep highway grade in the mountains just East of San Diego. Even though there’s a big 29-foot, Fleetwood RedLine toy hauler latched to the hitch, the 2500 Crew Cab 4x4 I’m driving is hardly taxed by the trailer in-tow.
My foot rolls deeper into the throttle and the speedometer needle in the new dash instrumentation climbs at a very satisfying pace — obviously a direct result of having 660-foot-pounds of torque rolling off the crankshaft of the 6.6L Duramax V8 diesel humming beneath the hood.
Back off the throttle and the Silverado settles down to a smooth, steady, quiet cruise speed of 65 mph — uphill.
Gary White, GM North America vice president and vehicle line executive of fullsize trucks — and one of my driving partners-says, “There’s not a broader, more powerful or more capable lineup of heavy-duty pickups in the industry.”
It’d be tough to find a point on which to challenge his assessment. At least that’s my impression after driving the 2007 GM Heavy Duty pickups — be that a Chevrolet or GMC, two-wheel-drive or four, long bed or short, Regular Cab, Extended Cab, Crew Cab or Dually.
These old bones ain’t what they used to be. But in reality, the bones really are the same. It’s everything else attached to the frame rails of GM’s HD truck/SUV line (the last vehicles to get the 2007 major make-over) that have changed.
The bodies are all-new inside and out; the engines have more power; and there’s a new transmission for the stout 6.0L small-block that serves as the base engine for the line-up.
BOLD HARD BODIES
The General’s all-new Silverado and Sierra 1500 Series (half-ton) pickups, the 2500 (3/4-ton) and 3500 (1-ton) Series Heavy Duty models have taken a big step forward in refinement. They are still hard-core work/play trucks, but are more civilized and well-mannered than ever before.
In recent issues, we’ve touted the new bodies and spacious interiors found in GM’s full-size SUVs and half-ton pickups. Those same attributes are found in the ’07 Heavy Duty models; each model’s cab is just as nicely laid out and comfortable as you’ll find in the other ’07 GM pickups and SUVs.
Although GM engineers left the frame rails alone, they have improved the brakes and steering which instills a lot of driver confidence regardless of the environment. The trucks just feel “right.” Where the most eye-catching changes show are in the bodies, which now show big differences between models and brands (Chevrolet/GMC) — most notably the front sheetmetal that conveys a much greater sense of power than their 1/2-ton counterparts.
The new grilles are more open than those found on the 1500 Series. The hoods are taller and vented, the headlights are slightly larger, and the front fenders wider and more rounded-all working in concert to convey a broad-shouldered, muscular look.
By the way, the new Dually has a one-piece stamped fender, which really helps smooth its distinctive lines.
A full line of GM accessories are available including this integrated bed storage system. The rails can support 500 pounds from each sliding mounting bracket. Diamond-plate storage boxes are offered in both polished and satin finish.
Those who worry about towing larger boats while keeping within the vehicle manufacturer’s weight-carrying limitations need not worry about such things with the 2007 Heavy Duty GM pickups. The weight-carrying limit is more than 12,000 pounds, so towing a boat like this 24-foot Ranger center-console is a piece of cake — especially with a Duramax diesel under the new bodywork.
Where the most eye-catching changes show are in the bodies, which now show big differences between models and brands (Chevrolet/GMC) — most notably the front sheetmetal that conveys a much greater sense of power than their 1/2-ton counterparts.
The new grilles are more open than those found on the 1500 Series. The hoods are taller and vented, the headlights are slightly larger, and the front fenders wider and more rounded-all working in concert to convey a broad-shouldered, muscular look.
The new grilles are more open than those found on the 1500 Series. The hoods are taller and vented, the headlights are slightly larger, and the front fenders wider and more rounded-all working in concert to convey a broad-shouldered, muscular look.
By the way, the new Dually has a one-piece stamped fender, which really helps smooth its distinctive lines.
SIX-SPEED SHIFTS
It’s what is under those sculpted hoods of both the GMC Sierra and Chevy Silverado HDs that really separate the men from the boys in the working pickup world.
The base engine is the 6.0L Vortec gas V8 with variable valve timing and other state-of-the-art technology that brings power output to 353 hp and 373 lb/ft of torque. Fuel economy, although not certified, is said to be in the neighborhood of 18mpg on the highway and near 14 in town.
Such fuel numbers — and the feel of a much more powerful engine from a stop — is a direct result of an all-new 6-speed automatic that replaces the 4L80 4-speed of yesteryear.
The Hydra Matic 6L90 has a stump-moving 4.03:1 First gear and a 6.04:1 overall ratio spread (the 4L80 was 3.31:1) — including a double overdrive that helps deliver an excellent balance of performance and fuel economy. Equally nice is the new six-speed offers manual gear selection with tap up/tap down shift control, a Tow/Haul mode, and smart Grade Braking, all which make trailer towing and hauling big loads a breeze.
The base engine for the ’07 Heavy Duty pickups is the 353hp, 6.0L Vortec V8 backed by an all-new Hydra-Matic 6L90 6-speed automatic with either 3.73 or 4.10 axle ratios. The upgrade ($8,500) is the 6.6L 365hp Duramax diesel and Allison 1000 sixspeed automatic with 3.73 axle ratios.
DURAMAX IMPROVED
But the real driving fun comes when you get the optional ($8,500) Duramax/Allison diesel package. The new Duramax 6.6L turbo-diesel is the most powerful diesel in the 3/4- and 1-ton pickup market with 365 horsepower and 660 lb.-ft. of torque.
GM’s torque monster is also one of the cleanest. My seatmate during one of the towing segments, Charlie Freese, the Executive Director of GM Powertrain and the hands-onexpert of the “new” Duramax, says the upgrades bring it to 2010 emissions standards while also improving its fuel economy and power.
The cleanliness is quite evident when you’re following one of the new diesel-powered GMs; there’s not a hint of black smoke, nor any hint of unburned diesel fuel.
Storage space is much greater in the new pickups, including a big, deep center console with storage under the armrest and a two-tier glovebox in models with the “pure pickup” cloth interior.
The new Duramax provides a 90-percent reduction in particulate matter and a 50-percent reduction in NOx (compared with current standards), meeting a new federal government emissions mandate that applies to all diesel engine manufacturers.
Freese explains such clean running comes as a direct result of computer-designed combustion chambers to burn the fuel more efficiently-and the incorporation of an ungainly-looking exhaust system that marries a bulky catalytic converter, muffler and particulate filter system into a very weird-looking tailpipe.
Freese explained the oddshaped exhaust tip greatly reduces the 800-degree exhaust that blows out of the particulate filter when it burns off the soot, or “regenerates,” while you drive down the road.
Without this odd-looking, air-cooled tailpipe, you’d probably burn the paint off the fender and roast anyone standing next to the exhaust tip when the regeneration process begins.
Most notable of the new Heavy Duty body changes are the big chrome bumper shoulders, slot in the lower bumper, taller hood and wider grille openings.
As for the fuel economy, Freese says in general, a turbo-diesel such as the Duramax will be about 25-percent more fuel efficient than a comparable gas engine when unburdened, and up to 70- percent more fuel-efficient when loaded down and running at higher elevations.
That said, we’d expect to see the new Duramax deliver about 22 mpg on the open road (unladen, of course) and close to 15 in the city. Not bad for a truck with a curb weight knocking close to 7,000 pounds.
TOWING STRENGTH
What hasn’t changed in the diesel powertrain is the renowned Allison 1000 six-speed automatic transmission. The Allison can be manually shifted if so desired, and it employs grade-braking and other features that quickly match driving conditions to vehicle speed, engine rpm and load.
Speaking of load, if you need to haul your heavy off-road adventure toys, the new GM heavy duty pickups are up to the task. All of the new Heavy Dutys are equipped with a 2 1/2-inch receiver hitch instead of the more conventional 2-inch found on the 1/2-tons.
That means 4x4 models with the gas engine can pull toy haulers and boats up to 12,400 pounds on the hitch ball without using a weight-distribution hitch. The diesels can tow up to 13,000 pounds, or, use a 5th wheel, and the HDs can pull trailers weighing up to 16,700 pounds.
Lest we mention the gas-powered Heavy Duty pickups have a maximum gross combined weight rating (GCWR) of a whopping 18,500 pounds, making the new GMs the towing leader in the 3/4 and 1-ton pickup class powered by a small-block V-8.
Interiors are shared with the full-size SUVs and 1/2- ton pickups. “Luxury-inspired” dash found in the upscale, leather-clad Silverado LTZ and Sierra SLT is different from that found in the lower-trim levels.
FINAL TAKE
Our overall impressions of GM’s refreshed and refined heavy duty pickups is one of a sweet-driving package.
Add in the option of getting the Z71 Off-Road 4x4 suspension that’s new to the HDs, and you can rest assured that if you are an off-road adventurer who needs a strong, refined truck for work — and an equally strong, yet comfortable toy hauler for those well-earned days off — you’d be hard-pressed to find anything better in 2007.
2007 GMC/CHEVROLET HEAVYDUTY PICKUPS AT A GLANCE
- 2500HD (three-quarter-ton) and 3500HD (one-ton) models
- 2WD and 4WD drivetrain in all models
- Three cab styles: regular, extended cab, crew cab and crew cab Dually
- Three box configurations: standard (6’ 6”); long bed & Dually (8-foot)
- Choice of 353 hp 6.0L Vortec gas or 365 hp 6.6L Duramax diesel engines with six-speed automatic transmissions
- Z85 smooth ride suspension or new Z71 Off-Road package (4x4 only)
- Distinct trim offerings, including two different interiors
- Segment-best gross combined weight rating of 18,500 pounds (6.0L)
- Segment-best conventional trailer weight rating of 13,000 pounds (6.6L)