By Heather Hogland & Kim Grimm
As they say, what goes up must come down! That is so true, especially when it comes to mountain grades. We cannot say it enough, you only get one chance to start down a mountain in the right gear! You need to make sure you do it in the proper gear for the weight you are carrying and the grade you are descending.
Grades are based on a decline of 1%, in other words for every 100 feet of road surface there is a drop of 1 foot. Using this formula, an 8% grade means that the road surface drops 8 feet for every 100 feet of travel over the distance posted. If the sign reads 8% grade 6 miles then it means that for the entire 6 miles that road will lose 8 feet of elevation per 100 feet of travel. In other words, you had better pay attention! Take it seriously.
I was recently on a two-lane road in Ohio. Imagine my surprise when I came upon a sign on a truck route I was following from my first drop to my second, which said 17% grade! Yes, 17%! This stretch of road is between I-271 and I-71. It is Highway 303 south and east of Cleveland and thank goodness it was almost midnight so there was no traffic. Headed east, I was going up the ‘hill’ and had to drop about 3 gears. I can’t imagine driving that road in the winter.
Actually, I have been on the steepest grades in my career on two-lane roads in eastern states like Pennsylvania, Virginia, West Virginia and New York. In the western states the steepest grades are oftentimes on those two-lane roads. Wolf Creek Pass immediately comes to mind, as well as running I-395 all the way from north to south. The narrow two-lane roads are not traveled as often these days by large trucks, but take all precautions when planning to use them. They do still have those large grades and sharp curves. Many times, at least out west, there will be signs saying large trucks are ‘not recommended’ which means you CAN use the road, but maybe you SHOULDN’T. Just a thought from a couple of experienced ladies who have BOTH taken Highway 198 between Highway 101 and I-5 in California at different times!
Sometimes these two-lane roads have run-offs or escape ramps ‘just in case’ you lose your brakes, some don’t. Also, always be aware there is probably a town a stop sign or a signal light at the bottom. I remember crossing Highway 166 in Maricopa, California and coming down a 7% grade where there was a stop sign at the bottom; so be aware! (California seems especially adept at putting towns or scales or signal lights at the most inappropriate places!)
Sometimes if you can understand exactly what the posted sign is telling you, it becomes much clearer WHY you need to follow the direction. When we started driving, there weren’t a lot of mentors around for us to get this information from and it is our goal to be able to be a resource for all of you.
Drivers expect to find steep grades in the mountain ranges out west, but we hope to make new drivers aware to be on the lookout for steep grades everywhere! The little orange/yellow diamond shaped sign with the little truck going down a grade is universal, it is used everywhere you will be travelling and will include the % of the upcoming grade. Heed the warning!
Stay Safe Out There and Keep It Shiny!
Heather Hogeland and Kim Grimm are CDL holders and longtime friends with a combined 75 years and 7 million miles of driving experience. Both are writers and have a love for everything trucking, as well as, furry, four-legged friends. Kim is currently a full-time owner-operator and part-time writer. Heather writes for various trucking publications and enjoys traveling with her husband Roger.