Avalanche SUT, new design, new engine

2007, Chevrolet, Avalanche

BLANCO, Tex. -- Narrow McCall Creek Road carves twisty chicanes into limestone embankments which ripple through the rolling Texas Hill Country. Over this contorted asphalt comes the 2007 iteration of Chevrolet's Avalanche, a big-rig vehicle stoked with a powerful engine and -- despite a bulk of nearly three tons -- capable of surprisingly nimble maneuvers.

It's also unusual in configuration, as there's the abbreviated bed of a pickup aboard plus the big cabin of a super-size sport-utility wagon with four full-size doors and two rows of comfortable seats for passengers. The jumbled configuration makes Avalanche a multi-purpose machine which functions as both a wagon and truck, thus explaining its descriptive tag of sport-utility truck, or SUT.

Chevrolet rolled out the original Avalanche as a 2002 model derived from Chevy's super-size Suburban SUV yet discarding Suburban's boxy rear bay in favor of the shortened bed of a pickup truck. Our test vehicle romping through the hills of Texas amounts to a new generation of designs for Avalanche 2007, based on the new GMT-900 platform of General Motors which also supports the big SUVs of GM -- Chevrolet Suburban and Tahoe, GMC's Yukon and the Cadillac Escalade.

The GMT-900 platform has boxed frame rails stretching from tip to tail to forge a firm foundation. Also, there's a wider track for front and rear wheels and a lower center of gravity for the overriding structure, which makes this Avalanche more stable in motion and, when coupled to a revamped suspension, improves the ride quality and the vehicle's ability to move through a set of curves without much body roll.

Actually, we're surprised by the agility and easy-driving nature of this Avalanche -- it doesn't behave like a gigantic truck that occupies more than 18 feet of real estate from nose to tail. With the new design for 2007, Avalanche contains a lot of new features with multiple V8 engine options including a flex-fuel plant which enables Avalanche to run on E85, the ethanol-mix renewable fuel.

Despite enhancements and new features, Avalanche comes to market with reduced prices. For example, the base edition 2007 Avalanche LS brings a MSRP of $31,615, while the 2006 Avalanche LS 2WD lists for $33,910, or $2,295 more. New styling for Avalanche's external package, so smooth now with clean lines which seem to diminish the scale, doesn't appear at first glance that different from the previous generation.

The sheetmetal is different, however, beginning up front with a fat-lip fascia fitted with square-hole foglamps and faux skid plates, a twin-port horizontal grille with narrow mesh insert, and squarish headlamp clusters covered by smoked lenses. There's a sharper rake to the windshield and a bulging power dome on the hood, squared wheelwells on flanks with subtle fender flares but smooth sides on the doors, save for a single strip of protective molding.

Wheels are bigger now, with the standard size bumped up to 17 inches and options reaching as high as 20 inches. The suspension is a new coil-over-shock arrangement up front and a five-link at the rear with coil springs. An optional Autoride rear suspension device employs continuously-variable road-sensing damping with air-leveling shock absorbers for precise control over bumps.

The steering system is a rack and pinion mechanism, not common among truck-based SUVs. It brings quick and predictable response from the steering wheel. Brakes consist of big discs on all wheels, with linkage to a computerized anti-lock brake system (ABS), traction control system (TCS) and GM's StabiliTrak yaw control.

Avalanche for 2007 offers trim designations of entry-level LS, well-equipped LT and top-tier LTZ with a choice of rear-wheel two-wheel-drive (2WD) or four-wheel-drive (4WD) traction. New features include cargo cover retaining straps, a tailgate with remote locking and unlocking, and a remote vehicle starter system.

But this new version retains a feature from the original edition which sets it apart from other vehicles: The back wall of the cabin also works as a door. It folds down flat after the back seat tumbles forward and forms a generous extension of the truck box, which grows from 63.3 to 97.6 inches. This back gate -- called a Midgate -- consists of three parts that include a window at the top, a mid-level brace and the composite lower panel.

You can drop the panel, leaving glass and brace in place and creating a horizontal portal to accommodate long and thin loads like tubular poles, lumber or 4x8 sheets of plywood. A three-piece rigid cargo cover tops the truck box and seals bed and contents from weather.

You may also detach the window and stow it in a special slot on the panel, then fold the panel with attached brace to completely open the rear space. That enables Avalanche to carry bulky items, such as a stack of sacks filled with building material like mortar, or a portable generator, a coupe of dirt bikes, even a big snowmobile or aqua scooter.

Or you could leave the Midgate locked in place but the rear seatback folded down to make a water-tight compartment stuffed with fragile goods while the truck bed in back carries other wares not sensitive to the weather. The standard engine for Avalanche 2007 is a 5.3-liter V8 rigged with GM's Active Fuel Management (AFM) technology which cuts by half the number of cylinders engaged in the combustion process when boosted power is not needed in order to conserve fuel.

Big engines generally denote a dog-thirsty appetite for lapping up fuel, but the AFM device is a real fuel-saver and turns Avalanche into a rather efficient vehicle. The plant generates big muscle -- 320 hp at 5200 rpm and 340 lb-ft of torque at 4200 rpm.

A flex-fuel variation delivers 310 hp at 5200 rpm and 335 lb-ft of torque at 4000 rpm. And the top plant is a hunky 6.0-liter V8 with AFM that nets 355 hp at 5400 rpm and 365 lb-ft of torque at 4400 rpm.

Safety equipment aboard ranges from frontal air bags for front seats to three-point safety belts for all seats and a tire pressure monitoring system (TPMS), with curtain-style air bags for both rows on the option sheet.

2007 Chevrolet Avalanche LT 1500 4dr Crew Cab 4WD SB (5.3L 8cyl) MSRP $35,295

By Bob Plunkett

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Images of the 2007, Chevrolet Avalanche

2007 Chevrolet Avalanche 4dr Crew Cab SB
2007 Chevrolet Avalanche 4dr Crew Cab SB
2007 Chevrolet Avalanche 4dr Crew Cab SB
2007 Chevrolet Avalanche 4dr Crew Cab SB
2007 Chevrolet Avalanche 4dr Crew Cab SB
2007 Chevrolet Avalanche 4dr Crew Cab SB
2007 Chevrolet Avalanche 4dr Crew Cab SB
2007 Chevrolet Avalanche 4dr Crew Cab SB