Gear Selection

The first thing to remember when descending a long, steep grade is to keep your gears low, generally no higher than the gear you ascended with. The low gearing will naturally help keep your truck at a lower speed, reducing the need for extensive braking that can cause you to end up in trouble. In some situations, a 55 MPH grade may require 20 or 25 MPH for a fully-loaded semi. Take your time, because losing your load takes much more time than a smooth, slow, controlled descent will.

Start out low and slow and maintain that speed to the best of your ability, knowing that you'll probably pick up more speed as you continue to roll downhill, whether you try to or not. Proper gearing can help keep you from picking up speed too quickly and ending up out of control. You'll want a combination of no more than 20-25 MPH and 10 PSI on the brakes to maintain it at that speed. If your truck is taking off at that point, you need to downshift to a lower gear.

Controlled Braking

No matter how great your brakes are, don't ride them. A relatively steady, light braking at around 10 PSI is usually about the limit that most drums can dissipate heat at effectively while avoiding brake fade. This includes your jake brake, as extensive jake braking is considered both rude as well as a sign of an inexperienced driver, and in some areas, can lead to fines. Many shops are capable of adjusting your jake brakes to kick in at particular speeds automatically, so consider having these settings adjusted for mountains if you're expecting a lot of high-grade driving.

When it comes to your regular brakes, you'll discover that they heat up during descent, leading to a phenomenon called brake fade. As the drums heat up and expand, the brake shoes often are no longer able to reach the drums, causing them to fail, even through reset and emergency options. Using other options, such as occasional jake braking, gearing, and starting with a low speed, can often provide you with great benefits including avoiding brake fade.

Runaway Ramps

No matter how many people you see in Colorado who are skiing down runaway truck ramps, that's not their actual purpose. Containing a mixture of loose sand, aggregate, and similar materials, these ramps are designed to rapidly decrease your inertia if your brakes fail or are ineffective on a mountain grade. They do an effective job of this, stopping your truck quickly and effectively without excessive damage to yourself and, hopefully, your load.

However, a runaway truck ramp is a stopping measure of last resort when you've lost control of your load and truck. They cause a lot of damage to your truck and in some areas, can lead to expensive fines, making your decision to ditch a very expensive one for you or your company. It's always a better idea to have your brakes checked regularly and adjusted for mountain use if you'll be crossing mountain ranges on a regular basis.

Best Practices for Long Descents

Remember, a fully-loaded semi can take more than a football field to come to a complete stop, especially on curvy, steep mountain roads. The last thing anyone wants to do is hurt or kill someone in another vehicle because they weren't in control of their fully-loaded semi during a steep grade. To keep your equipment, other drivers, and yourself safe, it's important to keep best practices in mind.

These practices include watching for grade change warnings, starting and staying slow, selecting the right gear for the slope, not riding your brakes, not using jake brakes excessively, using runaway ramps only when needed, and remaining cautious all the way down to keep the roads safe. When you keep these practices in mind, you can safely and effectively get through tough mountain driving conditions.

In Conclusion

Time on the road is always at risk of some type of harm or danger, but as OTR drivers, we know that it's important to keep safety at the forefront when dealing with tough driving conditions, including steep mountain grades. If you're getting ready for a trip over the Rockies or the Appalachians, just remember these key rules to keep your ride greasy side down and your wheels turning.