They're here, the final installment of GM's redesigned pickup truck line. Nowadays, few automobiles emanate more Americana than a pickup truck. And if a 1/2-ton pickup symbolizes the hard-working can-do American who is determined to get the job done through all types of terrain and weather conditions, then a 3/4- and 1-ton version are like John Henry without the heart attack.

You won't notice anything particularly inconsistent in the Silverado and Sierra HD with the pickups and SUVs that GM has been rolling out for over a year. The body styling is faithful to Chevrolet's and GMC's new design directions, except the new, heftier HDs look like 1/2-tons that had worked out for six months at the gym. The interior appointments-two interiors: "pure pickup" and a more luxurious trim level-adhere to the standards set by their smaller brethren with some added functionality. We have to admit that the body styling of the Silverado looks badass and burly compared to its cousin, the Sierra.

Aesthetics aside, performance is what stands out about these trucks. HDs are all about power and capability, and the new Silverado and Sierra heavy-duty pickups deliver that. Let's go straight to the Duramax diesel. Last year, when we conducted a shootout with the Ford, Chevrolet, and Dodge dualies, the Chevrolet stood out with its 650lb-ft engine. This year, GM has upped the ante by tuning the engine to make 660 lb-ft of torque, which is an impressive number that still pulls ahead of the competition by a nose. Both the gas and diesel engines are matched by a 6-speed transmission-an Allison in the case of the Duramax. The horsepower is nice, but it's the torque that gets the work done. During our preview of the vehicle, we raced a Ford by pulling an identical load up a steep grade and managed to beat it every time.

And the new Duramax complies with the latest stringent emissions regulations that are designed to bring diesel engines closer to the relative cleanliness of gasoline powerplants. Regulations demand a 90-percent reduction in particulate matter, 50-percent reduction in nitrogen oxides, and the use of the ultra-low sulfur fuel that recently went into national distribution. The previous formulations would lead to the fouling of the new emissions control systems. To accomplish this, the Duramax 6.6L uses a variable-geometry turbocharger, cooled exhaust gas recirculation, and closed crankcase ventilation to reduce nitrogen oxides in exhaust. Meanwhile, an oxidizing catalyst and particulate filter take out soot and other particulates and eradicate them by automatically burning them. Low-ash engine oil, more efficient cooling systems, new engine control software, and other approaches also contribute to making exhaust cleaner.

Interestingly, all of that gadgetry actually produces more noise pollution, which is forcing GM to come up with new ways to reduce the clatter-clatter of the diesels especially. The resulting engines are noticeably less obtrusive, both outside and inside, than the '06-model Fords and Dodges-and, we presume, last-generation GM HDs-that don't use the more tightly regulated powerplants.

There are a few things that stood out for us about these trucks. This will be the first model year that the Z71 off-road package will be available on an HD. Six-speed trannies come standard on all models. The trucks now have an integrated trailer brake controller, which was first used by the Ford Super Duty, but hey, a good idea is a good idea. The front seats now have pretensioners-which is not something we usually call out, but it's still interesting. The rear access doors on the Extended Cabs open wide at 170 degrees. Short, standard, and long cargo beds are available, as are the Standard, Extended, and Crew Cabs. The pure pickup trim level comes with a 6.1L capacity center console and a 9.1L capacity storage compartment underneath the back seats.

We like the diverse demeanors presented by the heavy-duty pickups now on the market. The sheetmetal and interiors on the Ford, Dodge, Chevrolet, and GMC products all look unique, and yet they perform oh so closely as the engineers in all of the companies try to squeeze every ounce of capability from their respective platforms. Chevrolet and GMC enthusiasts have nothing to fear about sticking with their brands. Super Duty and Dodge guys, you'll probably do Okay staying where you are, but it won't hurt to look at GM's heavy duty pickups. Toyota and Nissan fans? Well, what can we say? Those brands have a lot of catching up to do in the heavy-duty space. They better start running now. - Words by Mark Halvorsen

Cab Configurations
2500: Regular Cab, longbox; Extended cab, standard box
3500: Regular Cab, longbox; Extended cab, longbox; Crew Cab, longbox (3500)

Engines
6.0L V-8 Vortec (353 hp, 373 lb-ft)
6.6L V-8 Duramax diesel (365 hp, 660 lb-ft)

Transmissions
6-speed automatic (with 6.0L), 6-speedAllison automatic (with 6.6L)

Drivetrain
2WD or part-time 4WD

Final Drive Ratio
3.73 or 4.10 (6.0L), 3.42 (6.6L)

Suspension
Independent with coilovers(front), leaf springs (rear)

Brakes
4-wheel disc: 12.8-inch rotor (front and rear), power-assisted, 4-wheel ABS

Turning
2500 and 3500: Regular Cab, longbox, 45.3 ft
2500: Extended Cab, standard box, 47.6 ft2500 and 3500: Extended Cab, longbox, 52.5 ft
2500: Crew Cab, standard box, 51.2 ft2500 and 3500: Crew Cab, longbox, 55.1 ft

Curb Weight (2500)
Regular Cab, longbox, 2WD: 5,308 lb (6.0L), 5,980 lb (6.6L)
Regular Cab, longbox, 4WD: 5,554 lb (6.0L), 6,261 lb (6.6L)
Extended Cab, standard box, 2WD: 5,596 lb (6.0L), 6,330 lb (6.6L)
Extended Cab, standard box, 4WD: 5,847 lb (6.0L), 6,609 lb (6.6L)
Extend cab, longbox, 2WD: 5,735 lb (6.0L), 6,484 lb (6.6L)
Extended Cab, longbox, 4WD: 6,006 lb (6.0L), 6,756 lb (6.6L)
Crew Cab, standard box, 2WD: 5,742 lb (6.0L), 6,459 lb (6.6L)
Crew Cab, standard box, 4WD: 5,983 lb (6.0L), 6,718 lb (6.6L)
Crew Cab, longbox, 2WD: 5,899 lb (6.0L), 6,599 lb (6.6L)
Crew Cab, longbox, 4WD: 6,169 lb (6.0L), 6,906 lb (6.6L)

Curb Weight (3500)
Regular Cab, longbox, 2WD: 5,653 lb (6.0L), 6,353 lb (6.6L)
Regular Cab, longbox, 4WD: 5,837 lb (6.0L), 6,500 lb (6.6L)
Regular Cab, longbox, 4WD, dualie: 6,093 lb (6.0L), 6,756 lb (6.6L)
Extended Cab, longbox, 2WD: 6,007 lb (6.0L), 6,679 lb (6.6L)
Extended Cab, longbox, 2WD, dualie: 6,273 lb (6.0L), 6,945 lb (6.6L)
Extended Cab, longbox, 4WD: 6,271 lb (6.0L), 6,826 lb (6.6L)
Extended Cab, longbox, 4WD, dualie: 6,537 lb (6.0L), 7,225 lb (6.6L)
Crew Cab, longbox, 2WD: 6,193 lb (6.0L), 6,807 lb (6.6L)
Crew Cab, longbox, 2WD, dualie: 6,421 lb (6.0L), 7,065 lb (6.6L)
Crew Cab, longbox, 4WD: 6,436 lb (6.0L), 7,121 lb (6.6L)
Crew Cab, longbox, 4WD, dualie: 6,694 lb (6.0L), 7,371 lb (6.6L)

GVWR (2500)
9,200 lb (for all configurations and engines)

GVWR (3500)
9,500 lb (Regular Cab, longbox, 2WD)
9,700 lb (Extended Cab, longbox, 2WD)
9,800 lb (Crew Cab, longbox, 2WD)
9,900 lb (Regular Cab, longbox, 4WD; Extended Cab, longbox, 4WD; Crew Cab, longbox,
4WD) 11,400 lb (all dualies)

GCWR
Max Trailer Weight (2500 and 3500)
13,000 lb (conventional hitch, 6.6L, 3.73 final drive, 4WD and 2WD)

Payload (2500)
Regular Cab, longbox, 2WD: 3,892 lb (6.0L), 3,220 lb (6.6L)
Regular Cab, longbox, 4WD: 3,636 lb (6.0L), 2,939 lb (6.6L)
Extended Cab, standard box, 2WD: 3,604 lb (6.0L), 2,870 lb (6.6L)
Extended Cab, standard box, 4WD: 3,353 lb (6.0L), 2,591 lb (6.6L)
Extended Cab, longbox, 2WD: 3,465 lb (6.0L), 2,716 lb (6.6L)
Extended Cab, longbox, 4WD: 3,194 lb (6.0L), 2,444 lb (6.6L)
Crew Cab, standard box, 2WD: 3,458 lb (6.0L), 2,741 lb (6.6L)
Crew Cab, standard box, 4WD: 3,217 lb (6.0L), 2,482 lb (6.6L)
Crew Cab, longbox, 2WD: 3,301 lb (6.0L), 2,601 lb (6.6L)
Crew Cab, longbox, 4WD: 3,031 lb (6.0L), 2,294 lb (6.6L)

Payload (3500)
Regular Cab, longbox, 2WD: 3,847 lb (6.0L), 3,147 lb (6.6L)
Regular Cab, longbox, 4WD: 4,063 lb (6.0L), 3,400 lb (6.6L)
Regular Cab, longbox, 4WD, dualie: 5,307 lb (6.0L), 4,644 lb (6.6L)
Extended Cab, longbox, 2WD: 3,693 lb (6.0L), 3,021 lb (6.6L)
Extended Cab, longbox, 2WD, dualie: 5,127 lb (6.0L), 4,455 lb (6.6L)
Extended Cab, longbox, 4WD: 3,629 lb (6.0L), 3,074 lb (6.6L)
Extended Cab, longbox, 4WD, dualie: 4,863 lb (6.0L), 4,175 lb (6.6L)
Crew Cab, longbox, 2WD: 3,637 lb (6.0L), 2,993 lb (6.6L)
Crew Cab, longbox, 2WD, dualie: 4,979 lb (6.0L), 4,335 lb (6.6L)
Crew Cab, longbox, 4WD: 3,464 lb (6.0L), 2,779 lb (6.6L)
Crew Cab, longbox, 4WD, dualie: 4,706 lb (6.0L), 4,029 lb (6.6L)

Cargo Bed (Silverado and Sierra)
Standard: 78.7x50.6 inches
Long: 97.6x50.6 inches

Seating
2/3 or 5/6

2006 Ram 2500 Laramie Mega Cab 4x4April of 2006 saw the arrival of a spankin'-new Dodge Ram Mega Cab 2500. This Cummins-powered pickup had only 122 miles when it came to us wrapped in swaddling clothes. But this truck grew up fast and hard during the almost one-year and 30,000 miles that we have had it. We towed with it, hauled furniture across state lines, ran parts for projects, commuted in it, and tackled highways, deserts, and mountains both on and off-road-but mostly on. Now it's time to say goodbye to our hulking hunk of diesel power.

What We LikedGot Cubic Inches?: After a year of driving, our love of the rear passenger space of the Mega Cab 1500 didn't fade after our time with the 2500 version. Not only is the back of the cab large enough to fit bulky cargo and big-boned buddies, the seating and legroom is comfortable enough for sprawling wide and watching movies on the admittedly, teeny-weeny, flip-down LCD screen.

Tows Great: Newer powerplants from the Dodge, Ford, Chevrolet, and GMC brands may eclipse the '06 Ram's performance; but really, 610 lb-ft of torque hardly qualifies as anemic. We towed project pickups on a few occasions, over hundreds of miles, many hours, and only occasionally noticed that we even had a trailer back there at all.

Goes Far: You can't beat a diesel for its combination of usable power and fuel economy.

Let Your Fingers Do the Surfing: We may have never mentioned this before, but we like the audio system's steering wheel controls because they are located behind the spokes of the wheel. Granted, this hidden location requires that you use the buttons by touch, annoying at first, but they are easy once you get used to them and look a heck of a lot better in that they essentially are less visible than those clunky-looking buttons in other trucks.

UConnect: One of our staffer's became a real fan of this feature. L.A.'s long stop-and-go commutes often lend themselves to spending quality time with friends and family on the phone. UConnect uses Bluetooth to wirelessly connect to your cell phone and allows you to call, store numbers, redial, and use other features by voice commands, while listening to the conversation on the truck's stereo speakers.

Running Lights: That row of brilliant yellow roof-mounted running lights looks so red-necky sometimes, but they may have convinced more than one car to move out of our way as we barreled along with the visual subtlety of an 18-wheeler.

What We Didn't Like
Laramie Let Down: This premium trim package is comfortable and clean, but the competition hasn't stood still here. GM's premium interiors look higher-end, while Ford's attempt to differentiate with bold design makes the Ram interior look somewhat bland by comparison.

Turn the Key and Hope: Four different drivers of our Mega Cab long-term tester were left stranded when the Cummins diesel didn't start, click, or do anything. Frustration, tow trucks, dealer repairs, and choice four-letter words were all common themes when this problem arose during its year of duty.

That Danged Navi Unit Again: All three of our recent Chrsyler Group long-term loaners had the same navigation head unit, and all of them had problems. Luckily, the controls on the 2500's head unit didn't break like it did in its siblings, but the auto dim function stopped working, as it did intermittently on the others.

Apparently this was only a problem that one of our testers noticed, and it may be that user error was coming into play, but that's unlikely in this case. The screen on the navigation will not dim when the headlights are turned on, despite being set on "automatic." This necessitated the unit be switched to "manual," in order to avoid being blinded by the brilliant map display while driving after dark.

Fuel Prices: Cummins does get good fuel economy for such a powerful engine, but the price of diesel-in California, anyway-led to a recent $90 commitment to place 32 gallons in the tank. Ouch. This wasn't anything that any automaker had control over, but obviously the higher price of fuel will have a greater influence over why people may not buy a truck like this.

I'd Gladly Pay You Tuesday...: Got credit? The Mega Cab commands a premium for that extra space-about $6,000 more than a Quad Cab Laramie-as does that sturdy diesel powertrain. - Words and Photography by Mark Halvorsen

Glitches, Maintenance, MPG
Evaluation Period: April 2006 to March 2007
Odometer at Beginning of Evaluation: 122
Odometer: 7,906
* Scheduled Service: 7,500-mile service.
* Recall: Inspected for water in the fuel and installed roll-over
valve hoses.  
Odometer: 16,743
* Scheduled Service: 15,000-mile service.
Odometer: N/A
* Glitch: Five cases of the vehicle not turning over to start after
tuning the ignition and then starting moments, hours, or days
later. The control module was reflashed numerous times. At one
point, a control module and computer were replaced.
Odometer: 24,717
* Scheduled Service: 24,000-mile service
* Incidental Damage: Foglamp broken and replaced.
Final Odometer Reading: 30,768
MPG for Entire Evaluation Period: 15.3