1999 GMC Sierra 1500

What do you get when you take a Sierra (GMC) to the Sierras (mountains) in March? Snow. Ankle-deep.

That's what a handful of journalists encountered when we went to Yosemite National Park to drive prototypes of GMC's redesigned full-size pickup truck which goes on sale in the fall.

The snow was less of a surprise than the 1999 Sierra. Even though thinly disguised versions have been making their way around the auto show circuit since January, and even though its appearance is quite similar to the current model, the new truck is a quantum leap forward in function. It is bigger, quieter, more powerful, gets better mileage and stops with authority, something that could not be said of the old truck.

The new family of Vortec V8 engines make it feel like a Corvette engine is lurking under the hood, four-wheel disc brakes (anti-lock standard) are bigger and the cab has more room in both regular and extended versions. Even the wheels are bigger.

As with the Cadillac Seville, GM's stylists crafted a design whose exterior is very close in appearance to the vehicle it replaces. It has a sloping hood, cat-eye headlights and a large grille that dips into the front bumper for a bright, aggressive look that distinguishes it from the nearly identical Chevrolet Silverado. The wheelbase is 1.5-inches longer, driver ergonomics have been dramatically improved and the ride is more like a car than a truck.

The only thing they left out was a fourth door on extended-cab models. This would seem to be a major oversight when Dodge and Ford each offer four doors. Officials said a fourth door might be available next year.

General Motors sells more than 700,000 full-size GMC and Chevrolet pickup trucks, which tells you how important this vehicle is. Redesigning your best seller is the kind of job that keeps auto executives awake at night. Get it right and sales will soar; get it wrong and a huge chunk of business is jeopardized.

GMC is positioning the Sierra as a premium pickup, with more standard equipment than the Silverado. Even though I got to sample various models, I happened to spend the most time in an extended-cab Sportside with the 4.8-liter engine and automatic four-wheel drive. The leather, uplevel premium seats were better than many luxury cars. Not only did they have lumbar support that felt like a large hand holding my back, but the seatbelts were built into the seat so they always fit right no matter how the seat was adjusted. The regular seats were good, also, just not as adjustable. Seat travel is about one-third greater.

The extended-cab is 3.7-inches longer than before, and most of the extra room gives back-seat passengers usable legroom. The rear seat reclines 18 degrees and actually comfortable for a couple hours at a time.

The view out the front is panoramic, and side mirrors are huge. Visibility is also improved by larger side windows than the older truck.

From an ease-of-use perspective, the new instrument pane l is a winner. The gauge package resembles that of a Corvette. It is easier to see because the second-generation airbag in the steering wheel is smaller. There are warning lights for 18 functions as well as a readout for hours of engine use, critical to real truck users. There is also a readout for transmission fluid temperature, again a welcome feature for those who might do a lot of trailer towing.

Interior heating and cooling has been increased by 40 percent. It is quiet and efficient. On a cold morning, rear seat heat ducts gave warmer feet after only 15 minutes.

The Vortec V8 family has three new engines: a 4.8-liter, 5.3-liter and 6.0-liter. The 4800 has 255 horsepower, the 5300 has 270 and the 6000 has 300. The 5300 snaps to attention and revs furiously under heavy throttle. In a 0-80mph-0 acceleration and braking demonstration against similarly equipped models from Ford and Dodge, the 5300 was the clear winner time and time again.

These engines have so little vibra on they feel like overhead-cam units. I spent most of my time driving the 4800. Not only is it smaller than the engine it replaces, it makes more power and uses less fuel. It also takes up less space under the hood, which is why the cab can be bigger.

It handled itself well while climbing the hilly roads into the mountains. The automatic transmission has a Tow//Haul mode, which lengthens the time between gear shifts.

Underneath it all sits a three-piece frame made with individual hydro-formed section in the front and back. Not only is it lighter by 28 pounds than the old one, it is stronger and absorbs more energy in a crash. Repair costs would be less, as well, officials said.

Ride quality is exceptionally smooth, even in four-wheel-drive models. That is helped by the longer wheelbase and stiffer frame, which allows the suspension to be tuned for a more compliant ride. Ford and Dodge both have fairly new trucks, but it has been 10 years since GM redesigned theirs. When you come late to the party you can profit from the mistakes of others, and they have done so. Not only is it bigger inside, it has more power, rides better and is easier to use.

For a definitive evaluation I will wait for a regular production unit, but based on my time in a pre-production model, I can say GM has done its homework well and the results show it.

SPECIFICATIONS:

ENGINES: 4.8-liter V8
5.3-liter V8
6.0-liter V8
TRANSMISSION: automatic
WHEELBASE: 143.5 inches
CURB WEIGHT: 4,346 lbs.
BASE PRICE: not available