Largest Wheel Loader in the world

With 32 wheels, 16 axles and six programmable steering modes, the DBL-110 is, yes, fun to drive. We very carefully drove it along Everett's runway aprons, and it's surprisingly simple to operate-pick the right steering mode, and it's nearly capable of rotating around its own center axis. Pick another mode, and the loader crab-walks. "Here, let's put you in the air, " Dailey says as he raises the loader to its full 33-ft-high extension. The engines are now 30 ft below me, but the unladen DBL-110 remains stable and steerable. When you're hauling millions of dollars of parts along busy taxiways, it pays to be maneuverable.

* Rear-wheel-drive, six-wheel dump truck

HEIGHT: 23 ft 3 in. (at roof) | WEIGHT: 687.5 tons
ENGINE: 3370-hp 117-liter V24 diesel with 12, 170 lb-ft of torque

MEGA FACTOR: 3 ft 6 in. of ground clearance

It's just like the pickup in your garage-only this truck's torque equals that of a half-dozen semi tractors. The axle assembly (top) is the size of an F-150.

In the world of mining trucks, there's an ongoing dispute about exactly which one is the largest. Many of these beasts are equipped with electromechanical drivetrains, like a locomotive. But not this massive Cat. The 797B uses the same kind of direct mechanical drive as, say, a Chevy Silverado. So in terms of conventional powertrains, this is the largest. "It's just a big yellow truck, " says Mark Richards, marketing supervisor for Caterpillar's large mining trucks division. A big yellow truck powered by a V24 diesel that generates 3370 hp and a mind-boggling 12, 170 lb-ft of torque.

Driving the 797B is easy-once I get up the ladder that crosses in front of a radiator so massive it could double as a barbecue grill for the Jolly Green Giant. Inside the steel-fortified cockpit, I sit on a flat, squishy hydraulic seat facing a conventional steering wheel. My foot hits an accelerator pedal of normal proportions, and most of the instrumentation is familiar except for a digital readout that tells me how much tonnage is in the bed behind me. The engine's air starter screams until the immense V24 rumbles to life.

Put the seven-speed automatic into gear, and the truck initially lurches forward before lumbering off the line. It's then I realize that I'm almost 20 ft in the air, and what's behind me is three times bigger than any house I've ever lived in. The hydraulic steering has no feel, but it reacts quickly, and the 50 oil-cooled, 42-in. disc brakes could stop a runaway continental shelf. In fact, it's so confidence-inspiring that I'm tempted to become overconfident-not good when a mistake could mean picking the remains of my own Toyota Tundra out of the 797B's undercarriage. After thorough and thoughtful consideration, I think I'll keep my day job.

* 24-wheel, eight-wheel-drive mover

HEIGHT: 15 ft | WEIGHT: 90 tons
ENGINE: 400-hp six- cylinder Cummins diesel with 1000 lb-ft of torque

MEGA FACTOR: Three 90-gal-per-minute hydraulic pumps power four drive motors that move the vehicle over rails

It's just like the pickup in your garage-only this truck's torque equals that of a half-dozen semi tractors. The axle assembly (top) is the size of an F-150. (Photograph by John Burcham)