Going up a grade is easy—you just lose speed. The part that gets trucks in trouble is coming down heavy. If you've ever watched your speedometer creep up on a long descent and reached for the brakes, this is the article you want.

Pick your gear before the hill, not on it

The single most important rule of mountain driving semi trucks: go down in the same gear you'd use to climb, or one lower. You want your engine and driveline doing the work of holding the truck back, not your service brakes.

Set your gear at the top of the grade while you're still slow. Once you're rolling fast downhill, downshifting gets hard or impossible, and now you're stuck riding the brakes the whole way. Slow it down early.

  • Heavier load = lower gear. A loaded reefer or flatbed at near-max weight needs more holdback than a light van.
  • Steeper and longer = lower gear. A short 4% grade is nothing like a 7-mile 6% descent.
  • When in doubt, go one lower. Too low just means a slow, safe trip down. Too high means heat.

Brake strategy: snub, don't ride

Your engine brake (Jake) and your gear do most of the holding. Your service brakes are there for snubbing—short, firm applications to knock off speed, then release.

Here's the method: let the truck build to a set speed, apply the brakes firmly to drop 5 mph below it, then fully release and let the brakes cool. Repeat. Firm-and-release beats light-and-constant every time.

Riding the brakes lightly all the way down is what overheats them. Hot brakes fade, and faded brakes don't stop a loaded truck. If you smell them or they start grabbing, that's your warning—get to a pullout or runaway ramp while you still have options.

Chain law basics

Western mountain states post chain requirements in bad weather, and they're enforced. Fines are real, and so is getting shut down at a checkpoint for not carrying chains. Know the levels before you run a pass in winter.

  • Carry the chains. Many states require you to have chains aboard in winter months even when roads are clear.
  • Know the tiers. Requirements range from chains on drive tires to full chain-up including trailer axles.
  • Chain up in the designated area, early. Don't wait until you're sliding. Pull into the chain-up zone, do it right, and check your flashers.

Winter passes are also a judgment call. No load is worth a rollover. With no forced dispatch at ARI, you decide when to shut down and when to roll—your dispatcher works around your call, not against it.

The judgment that keeps you running season after season

Veteran mountain drivers aren't braver—they're earlier. Earlier on the gear, earlier on the chains, earlier on the decision to park. They check weather and pass reports before they commit, and they plan fuel and timing so they're not crossing a summit exhausted at 2 a.m.

Equipment matters too. Tires with real tread, a working engine brake, and well-adjusted service brakes are what let you run grades confidently. If you're running steep lanes regularly, keep your maintenance tight.

We keep more cold-weather and operations guides in the ARI resource center so you can run smarter in any terrain. When you run under ARI's authority, a dedicated dispatcher who knows your lanes helps you plan around weather windows instead of forcing you into a storm—and that's the kind of backing that keeps good owner-operators over the passes, load after load.