Constructed on the chassis of a Silverado LD truck with a cabin fashioned from the super-size Suburban wagon, Avalanche discards Suburban's rear bay in favor of the shortened bed of a pickup.

There's a husky V8 engine under the hood, a four-wheeling traction mechanism that automatically channels torque to all wheels, and a heavy-duty automatic transmission to manage so much power. 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.

The rear box has high walls and indentations to rig tiers or segment cargo, and a detachable tailgate folds down to extend the floor of the box. Three lock-down panels form a rigid cargo cover over the bed to secure contents.

A deluxe cabin in Avalanche resembles Suburban in a layout with seating for five or six. Avalanche comes in 1500 or 2500 series with rear-wheel-drive (RWD) or four-wheel-drive (4WD) driveline. The 1500 extracts power from a 5.3-liter V8 that generates 295 hp but the 2500 packs GM's 8.1-liter big-block V8 good for 320 hp. New exterior colors are available on 2004 models: Sunburst Orange, Silver Birch and Sport Red Metallic.

A pickup measuring up to the mid-size class debuts in Chevrolet's 2004 truck line. Called Colorado, the new truck shows up in nine models with three cab versions (two-door Regular Cab and four-door Extended Cab plus four-door Crew Cab), three suspension packages (standard, sport or off-road), and RWD or 4WD traction mode.

The Regular Cab has a bench clad in cloth or vinyl and divided 60/40, but bucket seats are optional. Colorado Extended Cab carries four doors and the Crew Cab also with four doors installs a folding rear seat with enough room to accommodate three adults in comfort.

Two new engines of in-line design where developed to propel Colorado. The base Vortec 2800 2.8-liter four-cylinder engine punches up 175 hp, while the optional Vortec 3500 3.5-liter in-line five-cylinder plant produces 220 hp. Options include heated seats and OnStar telecommunications, even side curtain-style air bags.

Chevrolet's compact-class S-10 truck for 2004 appears strictly in Crew Cab format with four doors and 4WD traction applied.

Powertrain is the Vortec 4300 V6 that makes 180 hp with a four-speed Hydra-Matic 4L60-E automatic transmission. The Insta-Trac 4WD system permits shift-on-the-fly switching from rear-wheel to four-wheel mode and has a 4WD low gear for off-road work. S-10 Crew Cab employs a cropped box of 55.2 inches to hold an easy-to-drive length.

A ZR5 Sport Appearance Package brings Spectra Gray wheel flares and bumpers, 15-inch aluminum wheels, bed rails and side steps, plus a roof rack. (CONTINUED...)