General Motors introduced the Envoy, TrailBlazer and Bravada in Baja in December. We got about 100 miles of driving on rough and fast Mexican two-lanes-flat and climbing, straight and twisting-and maybe eight laps around an off-road course with steep climbs and descents and 50-mph washboard trails.

We were able to bound past Mexican trucks on steep uphill two-lanes with excited confidence. With the engine's broad and bountiful torque, the transmission does dramatically less downshifting; during two-lane passing, the I6 leaves the surge in while taking the jerk out. And when the full-throttle upshift comes at about 6000 rpm the engine is only striding, not screaming. The smooth-shifting four-speed automatic transmission is the proven Hydra-matic 4L60-E, used in GM applications from Corvettes to Cadillac Escalades. Our test model was equipped with the standard 3.73:1 rear end differential; 4.10 for better towing and 3.42 for better gas mileage are available. Earlier we had driven a TrailBlazer with the 4.10, and the engine's torque buries any acceleration disadvantage with the 3.73.

Towing was a high engineering priority, and the Envoy is rated at 6200 pounds for 4WD, 6400 pounds 2WD. According to Ron Kociba, during GM's own testing, an Envoy blew away a Jeep Grand Cherokee V8 in a trailer-pulling race up a mountain. He added that it ran way cooler (thanks in part to that big seven-quart oil pan) and used 20 percent less gas.

And the faster the Envoy goes, the smoother it gets. With an official Mexican Highway Patrol escort along on the test drive, we felt free to squirt up to 100 mph, and found much to our pleasure how silky the inline engine is at 80 and above.

The chassis and suspension boast such racy things as rack-and-pinion steering, beefy four-wheel vented discs with twin-piston calipers in front, independent front suspension with short/long control arms, a solid rear axle using five-link suspension with Bilstein gas-charged shock absorbers and coil springs, plus thick antiroll bars front and rear. It was the first truck for the Envoy's chief designer, Ted Robertson, whose experience includes the '90s Camaro/Firebird. GM wanted his soul as well as his chassis knowledge in their midsize SUVs, and they got it. His goal was to put some "sport" in sport utility.

Robertson said he designed the Envoy to roll exactly five degrees in the corners, and then stop leaning. Because the vehicles in Baja were pre-production, there were some suspension discrepancies that taint any specific observations of the ride and handling-most notably, as Robertson himself only discovered near the end of the test, the rear coil springs were not the correct stiffness. But the ride was still very smooth, eminently car-like without being overly soft in the twisty parts.

Envoy's track is the widest in class, 2.2 inches wider than the 2002 Explorer between the front tires and 0.9 inch wider between the rear tires. This, coupled with a lowered mass from the engine position, drops the center of gravity. This could be a strong selling point, as the big issue with SUVs nowadays is their higher incidence of rollovers than sedans.

The Envoy offers an optional load leveling suspension, using electronically controlled air bladders fitted to the rear coil springs. It's intended to improve the ride while dealing with off-road nearly as well as the rugged coils. Road inputs are monitored by sensors that inflate and deflate the bladders independently, leveling the load horizontally as well as vertically.

The four-wheel anti-lock disc brakes are impressive. The front rotors are 12.0 inches and the rears 12.8, with a total swept area of 424 square inches. In addition, the aluminum front calipers are twin-piston. Under hard braking, we especially noticed that the Envoy's nose didn't dive, keeping the vehicle remarkably level and stable. However they seem to be susceptible to catching debris, especially off road. On three occasions over two days, we heard rubbing and loud squeaking, from our vehicle and another. However the problem might be easily cured-and may have been, in the two months between this introduction and vehicle production at its plant in Moraine, Ohio.

On an off-road course, we found that the Envoy with air springs bottomed quite easily on the dives, signaling that the optional skid plates are necessary for off-road driving. Our test model (equipped with 17-inch BFG Rugged Trail radials) had the skid plates, of course, which we also dragged in soft sand, chugging easily along at 5 mph in Auto4WD. Here is where the compromise appears to be buried. The bottoming was partially caused by a slightly low eight-inch ground clearance under the engine, a result of that clever tunnel through the oil pan for the front driveshafts, allowing that lower engine mounting for better balance on the road. But a ground clearance that's 1.2 or 1.3 inches lower than the competition (Explorer, Grand Cherokee) seems a reasonable and maybe even prudent payoff.

We had deliberately driven into that soft sand in 2WD, gotten bogged down, and switched to Auto4WD on the fly; it clicked and began pulling us right along again. On the higher-speed washboard surface, the rear end stayed impressively planted. On low-speed whoop-de-doos, the front end bobbed up and down more than we would have liked. This was with a pre-production suspension setup, however, and may be improved on vehicles at the dealerships.