At the rear, there's a convenient and practical step in the center of the rear bumper, sort of a big notch. But styling-wise, the twin round taillights stacked over the backup light at each corner are kind of lumpy and googly-eyed.

Overall, it looks sturdy and neat, with confident lines that express utility. The pillars and window lines are graceful, while the headlamps (split by the grille crossmember), taillights and turn signals are stylish. Big fender flares are used to visually express the vehicle's boldness, and may be either monotone or silver.

The most dramatic thing about the TrailBlazer may be what's not there: neither a V6 nor V8 engine. The new engine is called the Vortec 4200, an all-aluminum, double-overhead-cam, 24-valve inline six with variable valve timing.

Years ago Chevy trucks used an old reliable straight six, and Jeep has long used a more basic straight six in the Cherokee, while BMW and Lexus continue to use sophisticated versions in high-performance sedans. An inline engine is inherently smoother, simpler, more durable and more fuel efficient than a vee, although in times past, its superior physics had a hard time breaking out of its cast-iron shell. Advancements in electronics, metallurgy and manufacturing methods now enable an inline engine to soar, and for 2002 GM has fully exploited this technical opportunity.

The Vortec 4200 is no ordinary straight six. From 4.2 liters, it produces a stunning 270 horsepower, 30 more than Ford Explorer's new 4.6-liter sohc V8. And it has a very broad torque curve peaking at 275 pounds-feet, only 5 less than the Ford and coming 400 rpm sooner. It features electronic throttle control, an electrical system using silicon circuit boards (replacing some 1100 feet of copper wire), coil-on-plug ignition (thus no plug wires), and a seven-quart oil pan with a clever tunnel for the front drive axle, which allows the longish block to be mounted six inches lower, contributing to better balance and a lower center of gravity.

Attention to detail in other places is evident, from a battery box that draws in cooling air, to remarkably sanitary wiring under the hood, to rear-seat headrests that conveniently flip down for better rearward driver visibility. Because the engine is so quiet and smooth at idle, a feature called quot;intellistartquot; was added which prevents the starter from grinding if the key is turned when the engine is already running. With a mixture of amusement and pride, GM engineers report that this happened to them all the time during development.

The Autotrac system, standard on 4WD models, features four settings: 2WD, Auto4WD, 4HI and 4LO. In Auto, which shifts power to all four wheels as conditions require, the TrailBlazer can be towed without having to disconnect the driveshaft-a very convenient new feature. Switching in and out of 4WD can be done on the fly with a flip of the switch, although the vehicle must be in neutral to engage or disengage 4LO.

The chassis and suspension are also highly developed, featuring a list of sports car stuff: rack-and-pinion steering, beefy four-wheel vented discs with twin-piston calipers in front, independent front suspension with short/long control arms, solid rear axle using five-link suspension with Bilstein gas-charged shock absorbers and coil springs, thick antiroll bars front and rear. It was the first truck for the TrailBlazer's chief designer, Ted Robertson, who brought a resume to the assignment that includes the '90s Camaro/Firebird. GM wanted his soul as well as his experience in their midsize SUVs, and they got it. His