Part 1: [1] [2] [3] [4] [5] [6] [7] [8]
[Intro] [Truck Specs] [Dodge] [General Motors] [Ford] [Squat Test]

Part 2: Quarter-Mile Drags
[Intro] [3/4-Ton Unloaded] [3/4-Ton Loaded] [1-Ton Unloaded] [1-Ton Loaded] [F-450] [Diesel v Gas Comparison]

Part 3: Hill Climbs
[Intro] [3/4-Ton 7% Grade] [1-Ton 7% Grade] [Diesel v Gas Comparison 7% Grade]
[3/4-Ton 15% Grade] [1-Ton 15% Grade] [Diesel v Gas Comparison 15% Grade]

[F-450 All Grades] [Summary]

2007 GMC Sierra 2500 SLE Crew Cab 4x4

The GMC and Chevrolet heavy duty pickups are all new for 2007.

Our GMC Sierra came with the new 6.0-liter Vortec V8 gas engine that’s the standard power plant for GM’s three-quarter and one-ton pickups. It’s also the only gas heavy duty engine to offer variable valve timing and the first to have a heavy duty six speed automatic transmission. The extra gear it carries over the Ford and Dodge is aimed at providing improved fuel economy.

The ‘pure pickup’ interior of our Sierra had excellent fit and finish for a mid-grade trimmed heavy duty. The gaps between instrument, audio, and HVAC components were the tightest and best aligned of all the trucks.

The Sierra also came with an automatic mechanical locking rear differential. The other two trucks only come with limited slip clutches in their back diffs.

Our suggested improvement to GM for this truck – make the gas tank bigger. In the short box configuration it was the smallest in the group at only 26 gallons. The Sierra may have the best EPA-rated fuel economy of the trucks we tested, but this truck really needs at least four more gallons of capacity to extend towing range.

There’s a handy low-tech assist from GM on the Sierra (and Silverado) to help frequent tow-ers. Like the Fords, the Sierra has a 2.5-inch Class V trailer hitch receiver. But if you only need 2-inch Class IV hitch, the Sierra comes with a reducer sleeve to shrink the receiver’s diameter. Again, same as the Fords. What’s cool about the Sierra’s reducer, though, is that it has a ‘lip’ around the edges, so when you’re holding a hitch pin in one hand and a hitch shank/reducer combo in the other, you won’t have to worry about aligning the holes in the receiver and shank to thread the pin through. The lip physically indexes the hole alignments for you as you slide the shank into the receiver.  The Fords don’t have lips on their reducers, so you have to spend time holding and sliding heavy shanks back and forth to manually align the holes in the receiver, reducer, and shank. That can be tiring, very quickly.

The GMC was also the cheapest truck of our entire test fleet, at $36,693. That’s a good deal.

2007 Chevrolet Silverado 3500 LT Crew Cab 4x4

Even after seven years on the market, and four iterations, it’s tough to beat the well-integrated Duramax / Allison combination we had in our Silverado 3500. It took the pole position as the most powerful oil burner amongst our three one-tons, at 365-hp and 660 lb-ft of torque. One of our testers was so enamored with the powertrain we had to pry him out of the truck to drive the others, or grab the keys to this crew cab before he could grab them.

GM has made several significant changes to the Duramax architecture for 2007 – to improve durability and meet the new emissions requirements. It has a new ‘boreless’ turbo that allows the turbo shaft to be screwed directly into the compressor wheel instead of passing through it.

New fuel injectors allow for precise application of fuel up to five times during a single combustion stroke, reducing engine clatter and dynamically optimizing ignition to combustion conditions.

NOX emissions have been reduced by adding a larger exhaust gas recirculation (EGR) cooler and closed crankcase to contain engine gasses inside the motor.

Like the Dodge and Ford pickups, the Silverado also adds a diesel particulate filter (DPF) that requires periodic self-cleaning regeneration to burn off trapped soot.

The sinister looking black dually we drove also had a black cloth interior, with the ‘pure pickup’ dash and IP that’s so appropriate for a work truck like this. It was intuitive and ergonomically spot on.

Our biggest gripe about this truck was the placement of the integrated trailer brake controller. It’s low and on the left-side of the dash. Almost all aftermarket trailer brake controllers are added to the driver’s right side, higher up. Some drivers may struggle to automatically find the unit when they need to quickly increase gain.

Another observation about this dually, and the others, was how well mannered the truck was unloaded. The rear wheels stayed well planted on almost all road surfaces, mercifully giving driver and passengers a comfortable ride. We would have been bounced to oblivion in an unloaded dually 20 years ago.

Part 1 : [1] [2] [3] [4] [5] [6] [7] [8]