General Motors introduced the TrailBlazer and its two other midsize SUVs, the GMC Envoy and Oldsmobile Bravada, to the world's automotive journalists in Baja in December. Based on about 100 miles of driving on rough and fast Mexican two-lanes-flat and climbing, straight and twisting-and a few laps around an off-road course with steep climbs and descents and 50-mph washboard trails, the TrailBlazer might very well be as much truck as any SUV has ever been, and more car than any SUV has ever been-at least for the price. It eliminates the compromises. It is totally rugged and capable, while being totally comfortable and civilized. If you didn't know what kind of engine was under the hood, you might wonder. "Hmm ? this couldn't be a V6, too much power. It has the torque of a small overhead-cam V8 ? but it sure doesn't sound like one." It's so smooth that it doesn't sound like much of anything. And the faster it goes, the smoother it gets. With an official Mexican Highway Patrol escort along on the test drive, we felt free to briefly run the TrailBlazer up to 100 mph, and it was above 80 where the inline engine really showed the silky side of its character. It showed the beefy side down low. Our LTZ test model was equipped with the optional 4.10 rear differential, and was able to blast past Mexican trucks on steep uphill two-lanes with calm confidence. It leaves the surge in while taking the jerk out, because the burst of acceleration often comes without a downshift, as the ample low-end torque doesn't need it and therefore the four-speed automatic transmission isn't programmed for it. Ninety percent of the peak torque of 275 pound-feet is there at 1600 rpm-and it's still there at 5600 rpm. The full-throttle upshift comes at 6000 rpm, and the engine is still only striding, not screaming. The smooth-shifting transmission is the proven Hydra-matic 4L60-E, used in GM applications from Corvettes to Cadillac Escalades. Towing was a high priority with the TrailBlazer, which is rated at 6400 pounds on 2WD models, 6200 pounds on 4WD models. In Baja, the engineers couldn't stop raving about its capability. With genuine excitement (and glee), they boasted that during their own comparison testing, a TrailBlazer "ran away and hid" from a Jeep Grand Cherokee V8 in a trailer-pulling race up a mountain. They added that it ran way cooler (thanks in part to that big seven-quart oil pan) and used 20-percent less gas. They didn't say which rear end it had, the 3.73 or 4.10, but they did claim that towing would be no problem even with the long-legged 3.42. By the way, added chief engineer Ted Robertson, there's another 30 horsepower to be had just by going to dual exhausts. Aftermarket manufacturers are probably bending pipes now. On the stopping end, all you really have to do is look at the discs. There are four of them, all ventilated, and they are big: 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. Four-wheel ABS is standard. Under hard braking, we especially noticed that the TrailBlazer's nose didn't dive, keeping the vehicle remarkably level and stable. 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. Still, the ride was excellent, very smooth: in a word, carlike, without being too soft. It was designed to roll exactly five degrees in the corners, and then stop leaning. The amount of lean is often precisely selected and engineered, depending upon the anticipated buyers for the vehicle, and in this case Robertson chose that degree for a margin of comfort and security. As with horsepower, sometimes high-performance handling can get average-skilled drivers in trouble. The track is the widest in class, 2.2 inches wider than the 2002 Explorer in front and 0.9 inch wider in rear. 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. Among GM's three midsize SUVs, including the GMC Envoy and Olds Bravada, "The TrailBlazer is the one for off-road," said Robertson-it's the least luxurious and has the less-compromising coil-spring rear suspension, which, theoretically at least, keeps the rear wheels planted more firmly. We found that to be true on the offroad course, as the TrailBlazer was uncommonly and impressively stable on the high-speed washboard portion. It bottomed quite easily on the dives, however, signaling that the optional skid plates are necessary for offroading. 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. Another problem that appeared offroad, on two out of three short sessions, was a horrible squeak from the front rotors after they had passed through sand, mud and weeds-we even heard it once on another vehicle that hadn't been offroad. There's apparently something in the design of the brakes or calipers that allows debris to lodge in there. However it might be easily cured-and may have been, in the two months between this introduction and vehicle production at its plant in Moraine, Ohio. |
