Behind the Wheel of a Big Rig

Familiarity breeds content when sharing the road with 40 tons and 18 wheels

Mac Demere / autoMedia.com

Imagine you're motoring down a curvy backroad. It's so narrow that when you're 18 inches away from the fog line on the right, the left side of your vehicle is no more than that away from the centerline. Touching mirrors with passing vehicles is a real concern. Your brakes promise little stopping power. Your tires don't provide much grip, which is good—the vehicle is so top heavy that sticky tires would result in a tip over.

And you're going 120 mph.

At least that's what it feels like going 70 mph down a gently winding interstate highway behind the wheel of an 80,000-pound 18-wheeler. I've reached 155 mph on the German Autobahn—my first freeway experience in a big rig felt much faster.

Nervous Brake Down

Drivers of 18-wheelers are told to look at least 12 to 15 seconds ahead. On the interstate, that's about a quarter of a mile. If you're herding a loaded 53-foot trailer, 1,300 feet doesn't feel like a big cushion, and for good reason. Bringing a big rig to a halt takes about half again as long as the poorest-stopping SUV. (Consider that before cutting in front of an 18-wheeler.) And the trucker's confidence isn't helped by a half-second delay between when the driver goes for the brakes and pressurized air finally causes the brake shoes to contact the drums. (Your hydraulic brakes work instantaneously.)

In a big-rig, even mundane tasks, such as driving through a toll booth lane, become major challenges. Approaching a toll booth not long after I'd earned my Commercial Driver's License, I calculated that my truck was the proverbial camel attempting to go through the eye of a needle—we'd need a miracle to make it. Then I watched another truck successfully navigate the opening. I positioned my left mirror about four inches from the booth and cringed as I anticipated the impact of the right-side mirror. It didn't come. I asked my co-driver how close it was on that side. "Aw, ya had a couple inches." For a long time, when another big rig passed to my left, I had to fight the urge to tuck in my left elbow.

Double-Clutching

Shifting (behind only backing and navigating tight turns without running over curbs and mailboxes with trailer tires) is the most difficult skill to master. Virtually all big-rig transmissions are manual shift. Because the transmissions must handle so much power, most 18-wheeler transmissions—like racecar trannies—lack the synchronizers found on manual-shift production cars. So truckers are required to double-clutch when shifting both up and down the gears. Or else they shift without using the clutch.