Test Drive: Avalanche is a too-small temptress

— -- Chevrolet Avalanche, a version of the re-engineered full-size pickups and SUVs that General Motors began selling late last year, has a remarkably engaging driving persona and could be a terrific truck.

If the back seat had more room. And the front seats were more comfortable. And the fuel economy were better.

And the price for a deluxe version — the one with the stuff you want — weren't creeping so close to $50,000.

Despite those significant drawbacks, Avalanche has its allure.

• It no longer looks ugly. The redesign that it shares with all of GM's full-size trucks for 2007 helps greatly. Plus, Chevy discontinued the grotesque side cladding. Only about 20% were opting for the cladding after it was made optional in 2003, says Carl Hillenbrand, product manager for the Chevy Silverado pickup now; same job for Avalanche before that.

• It's clever, as always. The modified cargo box has deep, covered side compartments that will hold a lot of beverage containers, some groceries or truck supplies, such as spare oil, tow ropes and the like. They have drains, so you can fill them with ice and use them as coolers. The three-piece hard tonneau cover seals the cargo box, making it useful as an enormous trunk. It's a handful to take off or put back on, though.

The signature feature — movable passenger-compartment rear bulkhead — allows Avalanche to be used as a crew-cab (five- or six-passenger) pickup with short box (5 feet 4 inches) or a regular-cab (two- or three-passenger) pickup with long box (8 feet 2 inches).

To transform the truck, fold the rear seat cushions forward. Fold the rear back rest down. Unlatch the rear bulkhead and fold it down. That configuration, with the hard tonneau over the cargo box, provides secure storage for long items. You also can remove and stow the rear window for wide-open access.

• It's a new GM truck. That means it has a premium interior; a smooth ride; agile handling, especially for a machine of its size; and a collection of optional and standard features desirable enough that they can tempt you to overlook the drawbacks. For instance: GM's 100,000-mile powertrain warranty. OnStar emergency calling system. Remote-control engine start. Easy-to-program driver information center, trip computer and vehicle personalization system. Smooth, powerful V-8 engine. Easy-to-use four-wheel drive with automatic setting not found in other pickups.

That smooth ride largely is because Avalanche is based on the new GM SUVs, which use comfort-oriented coil springs on the rear suspension. Had it been based on the pickups instead, it would have been sentenced to leaf springs in back, and those can deliver a jittery ride, especially unladen. Tradeoff: The crew-cab Chevy Silverado pickup, depending on equipment, can carry from 336 to 717 pounds more than the Avalanche.

Think of Avalanche as a Chevy Suburban SUV with a cargo box instead of a third-row of seats.

Drawbacks:

•Four-speed automatic transmission. Cadillac and some GMC trucks have six-speed boxes, which typically boost fuel economy 5% or more vs. four-speeds. "Over the next couple of years you'll see us switch all our four-speeds to six-speeds as we get more availability," Hillenbrand says.

•Rear visibility. The tall tailgate and cargo box block vision, so the $250 rearview camera is almost mandatory. But you can only get the camera if you get thousands of dollars in other options, so your $250 feature raises the sticker price $5,255 or more, according to Chevy and Edmunds.com pricing lists. There's no camera and stand-alone screen package as Toyota offers for $695 on the new Tundra pickup. "We're looking at things like that for the future, to have a lower-cost camera system," Hillenbrand says.

•Front seats. Too much lumbar bump. You can't retract it fully as you can in some rival trucks. It feels better than in other GM full-sizers, but apparently that's an illusion, because Hillenbrand says the seats are the same.

•Fuel economy. Close to the window-sticker rating, but no better than any other big truck, 12 or 13 mpg around town, despite GM's "active fuel management" feature. Cylinder cutoff, it's called generically. It shuts off half the cylinders when they're not needed for smoothness or power. Honda, Chrysler and other GM models use it.

•Head restraints. None for the middle rear rider, a potential safety hazard. On the other hand, the safety belt for that slot is mounted to back of the seat, positioning it low and just about perfect for a youngster in a booster seat. Higher-mounted belts can drag across boosted kids' necks and faces instead of crossing their sturdy shoulders, as they should.

•Back seat room. Too little, despite the generous, 39 inches of legroom GM publishes.

It's a fair bet that if you buy an Avalanche, you plan it as a family vehicle, with lots of back seat room so the kids have squirm and sprawl space. You don't get it in any of the new GM trucks. They're all on the same platform, so have about the same-size back seats. And that size is too small.

Proof? Try the back seat of a 2007 Toyota Tundra CrewMax pickup. The specification sheets show 5 inches more back seat leg room in the Tundra than the Avalanche. But you don't need a spec sheet. Your legs and knees will tell the tale instantly.

Hillenbrand argues that there's plenty of room in Avalanche's back seat. He says some drivers might compromise it, though, by sliding the front especially far back: "The front seat has 2 more inches of travel, for tall drivers. We changed it at the request of our tall customers, of whom (GM CEO) Rick Wagoner is one." Wagoner is 6 feet 4 inches.

Still, Hillenbrand acknowledges, "We have been talking about the room in the rear of the Tundra (Crew Max) and are thinking about what that might mean for our future designs."

Even if Shorty is driving and the front seat isn't impinging on the back space, the rear-seat cushion sits too far forward. That narrows the space for getting in and out, as if the door opening were too small.

That rear-seat issue is a heartbreaker, because Avalanche and the rest of the new GM trucks are otherwise remarkably nice to drive and use.

2007 Chevrolet Avalanche

•What is it? Full-size, crew-cab pickup with short (5 feet 4 inches) cargo bed that converts to regular-cab truck with long (8 feet 2 inches) cargo bed. Available with rear-wheel drive (rwd) or four-wheel drive (4wd). Based on Chevrolet Suburban SUV platform. Manufactured at Silao, Mexico.

•How soon? On sale since April 2006.

•How much? $33,360 to $50,170, including $900 destination charge. Dealer discounting and a $2,000 Chevy rebate mean you should be able to buy for $1,600 to $1,800 less than dealer invoice, say edmunds.com and CarsDirect.com car-shopping websites.

•What's the drivetrain? Rwd models: 5.3-liter, iron-block V-8 rated 320 horsepower at 5,200 rpm, 340 pounds-feet of torque at 4,200 rpm.

4wd models: 5.3-liter, aluminum-block V-8 rated 310 hp at 5,200 rpm, 335 lbs.-ft. at 4,400 rpm.

Optional ($1,095): 6-liter, aluminum-block V-8 rated 366 hp at 5,500 rpm, 380 lbs.-ft. at 4,300 rpm.

All have four-speed automatic transmission and traction control.

4wd system has low-range setting and automatic setting that switches between rwd and 4wd as needed.

•What's the rest? Details on standard, optional and safety features at www.chevy.com. The site mistakenly hasn't listed the optional 6-liter V-8 but Chevy says it's working to correct that.

•How many? Chevy won't forecast. Sales tracker Autodata shows 64,000 the first 12 months.

•How big? Nine inches shorter, an inch narrower than a Chevy Silverado crew cab pickup. Avalanche is 221.3 inches long, 79.1 inches wide, 76.6 inches tall on a 130-inch wheelbase.

Weight is listed as 5,478 pounds (rwd) or 5,645 pounds (4wd).

Rated to carry 1,322 pounds (rwd) or 1,355 pounds (4wd). Rated to tow 8,000 pounds (rwd) or 7,800 pounds (4wd).

Turning circle diameter is listed as 43 feet, curb-to-curb.

•How thirsty? Under 2007 government formula:

5.3-liter V-8 is rated 15 miles per gallon in town, 21 mpg on the highway, 17 in combined driving with rwd; 15/20/17 with 4wd.

Using E85 ethanol fuel, rwd is rated 12/16/13 and 4wd is rated 11/15/13.

6-liter V-8 is rated 14/19/16 mpg with rwd; 14/18/16 with 4wd.

Under more-realistic 2008 formula:

5.3 is rated 14/20/17 with rwd; 14/19/16 with 4wd.

Using E85: 10/15/12 with rwd; 10/14/12 with 4wd.

6-liter, rwd is rated 13/18/15; 6-liter 4wd is rated 13/18/15.

Tank holds 31.5 gallons. Regular-grade (87 octane) fuel is specified.

Trip computer on 5.3-liter, 4wd test truck showed 12.7 mpg in suburban driving using gasoline fuel.

•Overall: Exceptional truck; versatile and pleasant to drive. But needs more back-seat room. A lower price and better mileage wouldn't hurt, either.