If you need a truck for your business, you aren't going to find one with a stronger work ethic than the 1998 Crew Cab Fleetside -- the biggest, baddest pickup truck ever to roll out of General Motors.You've got to love a truck with an engine that is warranted for 100,000 miles, that has as much interior room as your average Cadillac sedan and that has four rear wheels, four-wheel drive and that won't balk when you hook up a 7,500 pound trailer.This is truckin' USA.Although the Ford F-150 and Dodge Ram trucks are better in some areas than the Chevy, this machine becomes like a trusted friend, a partner. When you turn the key, you know you can depend on it to get the job done.Detroit may have slacked off with its cars, but America's automakers won't be messed with when it comes to their full-size trucks. There is nothing from any foreign automaker that can match the power, size and quality of the Chevrolet truck.PERFORMANCE, HANDLINGOur test truck came with a rumbling powerhouse of a motor, a 6.5-liter, turbocharged diesel -- a terrific engine for such a big rig.GM offers two versions of the diesel, one that makes 180 horsepower and one that is rated at 195 horsepower for all-wheel drive models. Neither seems like it would offer enough power to move this giant, 5,500 pound truck. But torque is the measurement of the force that spins the rear wheels, and few trucks have as much torque -- 430 foot-pounds -- as our maroon test truck.Acceleration is excellent, from a stop and when you need a little kick to pass slower traffic.The diesel makes a bit more noise than a regular gasoline engine, but it runs smoothly. I like that rugged, heavy-duty sound of the GM diesel engine. By the way, this is the very same engine that powers the Army's Humvee combat vehicles.Power comes on strong and keeps building evenly. The turbocharger kicks in seamlessly. Even when the engine is under heavy load, you almost never see smoke belching from the tailpipe. Performance is about the same as GM's 5.0-liter gasoline engine.GM beefed up its automatic transmissions for 1998 by changing the case and improving the internal parts. The four-speed automatic was already the best on the market, but now it works even more smoothly.Our test truck was a four-wheel drive model. But shifting to four-wheel drive was somewhat bothersome. You have to apply the emergency brake, put the transmission in neutral then lean forward and move a lever on the floor. Ford and Dodge let you shift electronically.An all-new version of the Chevrolet pickup, to be called the Silverado, is due out this fall. One hopes that it will offer electronic shifting into four-wheel drive.With a 168.5-inch wheelbase, I expected the test truck to have a ride as smooth as a 747 rolling down the runway.It was not so.Small bumps cause the Crew Cab Fleetside to shake, rattle and roll so much that Bill Haley and the Comets would feel at home. I t feels as if the suspension system is out of synch with the frame and body. I'd be willing to bet that the new frame and suspension under next year's Silverado will correct this roughness. This is the single biggest area of the Crew Cab that needs refinement.But driving this big beast is not so bad as long as you stick to the highway. Once you get the truck's cruise control set, the rig sails along effortlessly and smoothly. I put a motorcycle in the bed and hauled it to Valdosta, Ga. Crosswinds don't affect the truck's stability.The powerful front disc/rear drum brakes slow the heavy truck quickly when necessary. The power steering makes the truck easy to turn, but the 53-foot turning radius rules out sharp turns. In fact, this truck is nearly impossible to park in a regular angled parking space, such as at a grocery store or mall.FIT AND FINISHWe've seen photos of the next generation Silverado. The exterior won't be changed much.Howev er, if the new Silverado is going to regain the sales title for Chevrolet, GM is going to have to do better on the inside.The big, boxy dash must go, and the air conditioner must be made more efficient. It huffs and puffs and blows hard, but not enough air comes out to cool the interior quickly.Our test truck came with sumptuous leather seats that were comfortable on long trips. The power adjustment on the side of the seat made it easy to change the height or angle.I have no gripes with the way the Crew Cab Fleetside was assembled. There were no manufacturing flaws, and everything operated efficiently except the air conditioner. But the inside seemed dated. The switches and gauges have been around forever, it seems.As you might expect from the $37,000 price tag, the Crew Cab Fleetside comes with everything: CD player, a full menu of power accessories, a bed liner, cargo lights and more.If I had a job that required me to haul cattle trailers or move other heavy cargo and people, this truck would be near the top of my list. Despite the fact that it may not be as up to date as the competition, it has a rugged, invincible feel to it. My guess is that it will take many years and many hundreds of thousands of miles to wear it out.1998 Chevrolet Crew Cab Fleetside Pickup Base price: $25,323Safety: Driver's side air bag and anti-lock brakesPrice as tested: $37,654EPA rating: N/AIncentives: NoneTruett's tip: The Crew Cab Fleetside is a monster of a truck that is built for work. It's really too big to be used for everyday transportation.