Killer Hills

Loveland? Vail? Monteagle? Western slopes rank as the most challenging, especially in snow.

Where are the toughest hills? Mostly in the West, where engineers have paved grades of 8 percent and higher. While truckers differ in their choice of the most challenging inclines, they agree that weather, equipment and experience can make a big difference in how you handle any hill.

“Most of your worst grades in terms of putting strain on the equipment or working on the driver’s nerves are off the interstate system,” says owner-operator Robert Dubonnette of Lemoore, Calif. “Especially in the winter, not because they’re tough, but because they’re less traveled, don’t have runaway ramps, and aren’t as plowed and salted as the interstates.”

Take Colorado’s Loveland Pass, the 12,000-foot U.S. 6 hazmat bypass around Eisenhower Tunnel on I-70. U.S. Xpress driver Michelle Wolverton of Oklahoma City recalls her first trip over the narrow, two-lane pass. “Everything was fine until I got above the tree line and looked down over a sheer drop-off. I swear, it looked like it was 50 bazillion feet straight down,” Wolverton says. “That’s when I noticed the edge of the road getting crumbly. I think I screamed out loud right then.”

Loveland is second on Michael Millard’s list of worst hills. “I did Loveland Pass for Klein tankers, taking fuel from Denver to Dillon, Colo.,” Millard says. “I also pulled hazmat loads from Los Angeles to Denver with placards that required the detour over Loveland.” For Millard, now a safety specialist with the Federal Motor Carrier Safety Administration near Chicago, the worst hill is another in Colorado: 11,000-foot Red Mountain Pass on U.S. 550 between Silverton and Ouray. “Monarch and Wolf Creek are long and tedious,” Millard says. “However, Loveland and Red Mountain are bigger hills.”

Monarch, the 11,312-foot pass where U.S. 50 crosses the Continental Divide in Colorado, is “a pretty grueling ride, even in good weather, especially going west,” Dubonnette says. He says Monarch’s west side has a 7 percent grade for 9 miles with two hairpins at the end. “It’s challenging in the winter,” says Dubonnette, who pulls a tanker for Quality Carriers with his 1997 Freightliner Classic.

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One of the most infamous hills is Wolf Creek Pass, at 10,850 feet, where U.S. 160 crosses the Continental Divide through southern Colorado’s San Juan Mountains. “I remember old Wolf Creek Pass, before it became an eight-lane highway,” says Flying J company driver Dan Galligan of Pomona, Calif. “Back in the late ’60s it was two very narrow lanes of tight curves – not quite switchbacks, but tight nonetheless.” Other hills demand your close attention, he says, “but none compares to the old Wolf Creek Pass.”

Not all the toughest hills are in the West. “I’ve been on two-lanes in the Appalachians where you’d swear you were looking at your own trailer lights when you rounded a curve,” says owner-operator David Hein of Good Thunder, Minn.

“I’ve heard Fancy Gap is a good hill,” says Dubonnette, referring to a 7-mile, 7 percent grade on I-77 in Virginia just past the North Carolina state line. Uphill, Fancy Gap is a strain. Downhill it’s long, steep and curvy, and the North Carolina scales are at the bottom.

Two other infamous eastern hills are Black Mountain, a long grade of 4 percent to 5 percent on I-40 in North Carolina, and Tennessee’s Monteagle, which is 6 percent for 3 miles eastbound on I-24. Both hills have brake-check stops and decreased speed limits for big trucks.

Interstate hills will strain a max-loaded truck, says owner-operator Ramona Nelms of Cullman, Ala. “I’ve climbed all of them fully loaded, and on each one I get down to 25 mph or less,” Nelms says. Her list of tough climbs includes Soldier’s Summit on U.S. 6 east of Provo, Utah, and Tehachapi Pass on California 58 east of Bakersfield.

Nelms takes her Kenworth T600 up Tehachapi every week. “You wear yourself out changing gears,” she says, and California’s 55 mph truck speed limit doesn’t help. “You start out slow at the bottom, and you’re going to be at 25 miles an hour by the time you get to the top. That’s extremely rough on an engine.”

Her list includes Snoqualmie Pass on I-90, about 50 miles east of Seattle; Cabbage on I-84 in Oregon, east of Pendleton; and Oregon’s North, Middle and South Sisters west of Bend, each higher than 10,000 feet.

Nelms says she almost regretted one shortcut across Highway 242, about 5 miles from North Sister. “If you make a mistake on these, you’re going over, and there’s nothing but a big drop-off.”

Wyoming has its own set of widely respected Sisters, though they don’t compare to Oregon’s. “It’s three grades, one right after the other, on I-80, east of Evanston and west of Fort Bridger,” Galligan says. “They’ll tax a motor, and if you run flatlander gears, you’ll hate those hills, but they aren’t that bad.”

Sherman Hill is farther east on I-80, between Laramie and Cheyenne. Parley’s Summit is farther west, in Utah, before the I-80/I-84 split.

“I personally hate Vail Pass,” says C.J. Norris, a former Dick Simon Trucking company driver who’s now a student in Bradenton, Fla. “But any mountain can be scary if, for one reason or another, the driver loses control, whether it’s mechanical failure, driver error or Mother Nature playing with humans.”

Even with good equipment, weather can turn a tough hill into a nightmare. Owner-operator Hein refuses to run his 1995 Pete 379 in “the mountains at night during inclement weather,” he says. “During the day, I’ll only run them if the roads aren’t too slick.”

Weather, more than grade, produced the scariest hill experience for owner-operator Brian Alden of Harley, Ontario. He recalls descending Montreal River Hill on Ontario’s Trans-Canada Highway 17 between Sault Ste. Marie and Thunder Bay. He was driving his 1980 Freightliner cabover down a 6 percent hill in heavy, wet snow, hauling a 100,000-pound load of uranium, when he discovered his trailer brakes had frozen.

“The tachometer and speedometer needles were both buried at the top end as I flashed by another truck,” says Alden, who has 27 years’ experience. “The driver asked over the CB if I’d gone nuts. I said my brakes were gone. He radioed ahead there was a runaway and for everybody else to clear the highway. I was scared half to death: cold sweats and the works. On one side was Lake Superior; on the other was rock face. I decided I’d have to take the truck into the rock face to stop it, which was better than taking that uranium into the lake.”

The four-lane road had only mild curves and no divider, giving Alden room to maneuver.
“Using the whole road, I eased way wide for the curves and, like a race car, took the straightest possible line through them, drifting out very wide again on the way out of the curves,” he recalls.

“It worked out OK, but it still gives me the shivers.”


  • Do a thorough pre-trip inspection, and complete safety-related repairs before rolling. Are the trailer brakes frozen? Will the moisture in the brake lines freeze at higher altitudes? Do the brakes or steering pull? Do the cooling fan thermostat and the windshield defroster work? Are the wipers good?
  • Know your route in detail, down to the road surface.
  • Know the weather where you are and where you’re going at the time you’ll be there.
  • Know your load’s weight and stability.
  • Know your truck’s capabilities in relation to your load and the hill. At what rpm does your engine produce peak torque?
  • Know how to chain up. How-to manuals make it seem easy, but practice if you’ve never done it.


  • Downshift as needed to keep engine speed at peak torque output.
  • Communicate with CB and lights. Use four-way flashers under 40 mph unless otherwise posted.
  • Be courteous to other drivers climbing faster with lighter loads.
  • Frequently note coolant, oil and transmission temperatures. Ease up, if necessary, to avoid overheating.
  • Keep moving. Starting from a dead stop on an upgrade is dangerous and strains equipment.


  • Plan your descent according to your truck’s limitations and capabilities.
  • Communicate with CB and lights. Use four-way flashers under 40 mph unless otherwise posted.
  • Adjust brakes before starting down. Don’t trust auto-adjusters.
  • Never come down a steep grade in high gear. Downshift before starting down.
  • Use the transmission and engine brake as much as possible to maintain a safe speed.
  • Stop at the first sign of smoking brakes and be ready to grab your fire extinguisher. Very hot brakes could burst into flames upon stopping.
  • Notice the weather, traffic and terrain. Have an emergency plan.
  • Maintain extremely long stopping distances in traffic.
  • Long slopes are deceptive. Make sure you really are at the bottom before grabbing higher gears.

February 2000: my first day at a new job. I discovered an air leak before leaving the terminal and told mechanics and the dispatcher about it. They were not concerned. Not wanting to cause a fuss so soon, I took the truck out – and soon learned a vivid lesson.

It was a cool, sunny evening. I was at 78,000-plus in an International cabover without Jakes, hauling 7-foot roll stock. East of Buena Vista, Va., on U.S. 60, I came to Murphy’s Pass, with 8 percent grades for 8 miles, 15 mph hairpin curves and jagged rock or drop-offs hugging the white lines.

I chose sixth gear, crept around hairpins, worked the brakes and forgot the air gauges. Two-thirds of the way down the hill the dash buttons popped. The truck was a runaway.

There was a shoulder at that point, so I rode it, smacking branches and bouncing around, but the truck still went faster. Another hairpin, especially with oncoming traffic, meant ditching into the woods and 22 tons of roll stock breaking loose.

But the hairpins were all behind by then, and there was no traffic. I bumped and wrestled the truck around a few wider curves and rolled to a stop in downtown Buena Vista, brakes smoking heavily.

Worried about fire, I raced the engine, got the air back up and rolled slowly off. The lone traffic light before the I-81 get-on ramp mercifully stayed green. I rolled up the ramp and kept on trucking.

Mechanics and dispatchers do not deal hands-on with runaway trucks or with the possibilities of killing others and being killed. These are realities for drivers, who cannot afford to shirk responsibility for their truck’s mechanical condition.

Owner-operator David Sanborn of British Columbia says his truck is made for pulling hills. And well it should be. “Winter trucking in British Columbia is not for the faint of heart,” he says. “Eight percent is what I’d call a standard grade.”

P.K. Kwatashin of Lyle, Wash., once used prayer and coffee to haul transformers up a 15 percent grade on a mining road near Kitimat, British Columbia.

“I got halfway up and broke traction,” Kwatashin says. “There I sat, past active logging areas and 70 miles from the mine site. I sat and prayed, ‘Lord, no human power will get me up this hill. It’s up to you.’ I put the transmission in low-low and slowly let the clutch out and eased up the hill. Sat back and poured a cup of coffee and enjoyed my 30-minute ride to the top.”

Sanborn drives a 2000 Sterling with a 500-hp Cat 3406E, 1850 pounds-feet of torque, an 18 double-over transmission and 4.11 rears.

Sanborn says the steepest grade he’s ever heard of is on Highway 20 going into Bella Coola, British Columbia, on Canada’s west coast. “It’s 4 miles and 21 percent,” he says. Sanborn says drivers hauling “super B trains” – a standard tractor with a 32-foot, three-axle lead and a 28-foot, two-axle pup that Canada law maxes at 140,000 pounds – drop the pup atop the hill, deliver the lead, then go back for the pup.

Sanborn says Canadian law requires snow tires during winter, and officials are hardly overzealous about posting notices about chains or grades. “There’s 6 or 8 inches of snow, and they won’t have the chain light on,” Sanborn says of Rogers Pass, a two-lane road not to be confused with Rogers Pass in Montana. He says Canada’s Rogers Pass, just east of Revelstoke, British Columbia, on Trans-Canada Highway 1, is 8 percent for 2 miles on the west and 6 percent to 8 percent for 5 miles on the east.

“They won’t even post a grade unless it’s 5 percent,” Sanborn says. He says one hill, on Highway 93 near Radium Hot Springs, British Columbia, is posted at 11 percent on both sides.

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