I recently drove my 29’ Class C RV over two mountain passes in one day. I climbed from sea level to over 7000 feet, back down to about 4000 feet, back up to 7000, and finally down to 4000’ again. This is a lot of work for a six-and-a-half-ton RV built on a van chassis. And as my brakes smoked and spewed the toxic odor of burning brake pads, I realized I had a lot to learn about driving a big Class C Motor Home on mountain roads. The more I drove, the softer my brake pedal became; I had to push it almost all the way to the floor to slow down. I eventually pulled over to let the brakes cool and that helped, but it didn’t take long for the pedal to get spongy again and by the time I reached the bottom of the grade I was barely stopping at all. (You can read the whole harrowing story here). I was able to get to the bottom safely by pulling over to let my brakes cool and using low gear, but it was nerve-wracking, to say the least!
Once I was on flat land again I did research to learn what I’d done wrong to make my RV brakes overheat and fade on the mountain passes. Here is what I learned.
Know Your Route and Prepare Ahead of Time!
I’d driven my Class C RV on plenty of mountain passes in the Sierra Nevada’s, so when I glanced at the Google map and saw the squiggly lines of switch-backed mountain roads, I thought “piece of cake”. What I learned that day is that not all mountain passes are alike. Everything from the length of the grade, steepness of the grade, road conditions and weather can impact travel on mountain roads.
The Lesson: Plan your route ahead. Ask others or do research on the route before you go. My mistake was doing both passes in one day. The grades on both were very steep and very long, causing me to use my brakes a lot! I should have done one pass and rested my brakes at least a couple of hours before tackling the next one.
Safety First – Know the Condition of your RV
The one thing I had going for me that day is that I’d recently replaced my front brake pads, calipers and rotors. My rear brakes had been inspected and the drums replaced. I knew my brakes were in good shape. So, as I was mentally trouble-shooting what was causing my brakes to slide and smoke, I could deduce they were overheating. However, “to safely control a vehicle, every braking mechanism must do its share of the work. Brakes with excessively worn pads or rotors will not provide the same degree of braking power. If you are not sure about the condition of your braking system, have it inspected by qualified service center.” (Source: FMCA, “Mountain Driving: Let Your Engine Do the Work”)
The Lesson: Keep your vehicle maintenance up to avoid dangerous or even deadly RV brake or engine malfunctions on dangerous roads. If my brakes had been old and worn out, a caliper had gotten stuck or I had a brake fluid leak my situation could have had a very different ending.
Use Your Motor Home Engine to Slow You Down!
You should also “shift into low gear before starting the downgrade”, advises the Family Motor Coach Association (FMCA). FMCA also states, “with motorhomes, a rule for choosing gears has been to use the same gear going down a hill that you would to climb the hill. However, new motorhomes have low-friction parts and streamlined shapes for fuel economy. They may also have more powerful engines. This means they can go up hills in higher gears and have less friction and air drag to hold them back going down hills. For this reason, drivers of newer motorhomes may have to use lower gears going down a hill than would be required to go up the hill.
Usually you want the lowest gear that will keep the motorhome at or near the speed you want in negotiating the downhill. For example, if you’re going down a six-percent grade and wanted to go 35 mph, you would start downshifting and using the brakes to get to an engine rpm that will enable you to maintain a speed at or near 35 mph.”
The Lesson: I drove a stick shift for years and if my RV was a manual shift, downshifting would have been a no-brainer. But with an automatic transmission, I’m always unsure when I should shift into low gear. A rule of thumb, according to RVers Online who attended an RV Driving School is that if your “RV accelerates more than 5mph going downhill then you need to shift to a lower gear”. How helpful! I will be remembering that!!
Proper RV Braking on Steep Downgrades
RV and Motorhome brakes overheat from excessive use – or “riding”. Riding your bakes on long steep downgrades will cause your brakes to fade- or with consistent use, to stop working completely.
The Lesson: The goal for safe RV and Motor Home driving on mountain roads is to keep the brakes cool enough to keep working. You can do this by letting up on them for 3 seconds for every 1 second of application. (Source RVersOnline.org)
What to Do if Your Brakes Overheat
If you’re driving your RV or Motor Home down a hill and notice smoking, burning brake odor and/or brake fade, pull over as soon as you are able to do so safely and let the brakes cool. Turn off the engine and test the brake pedal if, after sitting a while, the sponginess disappears and the brake pedal becomes firm again, most likely your issue is brake overheating. It’s best to let your brakes cool completely before getting back on the road; that could take an hour or more depending on weather conditions.
Overheating your RV brakes can cause permanent damage to your pads, rotors and calipers. If you do overheat them, it’s best to get them checked out by a brake service center as soon as possible.
Do you have any RV driving safety tips you’d like to share? Or how about a scary story to share? Leave your comments below!