Mountain Driving: The art and science of mountaineering

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This story stems from a horrific truck crash that occurred on Interstate 70 near Denver, Colo. in late April 2019. An apparently out-of-control truck careened down an 8-km stretch of steep highway at 135 km/h before slamming into a line of stopped traffic.

Four people died in the ensuing inferno. A dozen others were seriously injured. The speed limit for trucks on that hill is posted at 70 km/h, yet witnesses have video showing the truck scorching past a runaway-truck ramp at well over 100 km/h.

Truck driving mountain
Most newly minted truck drivers have yet to see the mountains. (Photo: istock)

Published reports indicate the driver, 23-year-old Rogel Lazaro Aguilera-Mederos of Texas, had his commercial driver’s licence (CDL) for less than three years and had only recently operated outside his home state.

There’s no indication of how much mountain driving experience he had, but it’s safe to say he didn’t get any mountain-related experience when took his CDL course in Houston. If anything, he may have read the 1.5 pages on the subject in the Texas CDL training manual.

Which isn’t much different from what many Canadian CDL trainees get.

“Far too many commercial drivers today bet the house while descending steep grades.”

– Larry Hall, owner-operator

There are few areas in this country that have hills, never mind mountains, big enough for related training. That said, many newly minted Class A and Class 1 drivers eventually find themselves in places like B.C. and Colorado and Western Pennsylvania and West Virginia without the benefit of a thorough understanding of how to manage long downhill grades in heavy trucks.

“Far too many commercial drivers today bet the house while descending steep grades,” says Larry Hall, a veteran B.C.-based owner-operator and organizer of a group calling itself ADEPT (Assembly of Drivers, Educators and Professional Truckers).

 “Equipment today provides a false sense of security. With upwards of 600 horsepower of engine-braking ability, there seems to be little or no concern for the ‘what if’ scenario. What if the engine brake fails? What if you come around a corner and traffic is stopped, or there is an animal standing in the lane? Those drivers have no Plan B.”

Limits of entry-level training

Entry-level driver training is a hot topic today in Canada. While most agree that it’s a step in the right direction, entry-level training is just that. Mountain driving, like winter driving, is an advanced driving skill.

“Mountain driving requires a level of skill higher than most entry-level drivers can safely manage,” says Ed Popkie, president of the 5th Wheel Training Institute in New Liskeard, Ont.

“Our students graduate with the skills they need to safely handle city, highway and regional work. Asking them to cope with mountains at that early stage of their learning curve would probably be too much for most entry-level drivers.”

Popkie says there have been a greater number of truck crashes on Ontario’s Hwy. 11 between Martin River and Hearst in recent winters, many of which he attributes to inexperience.

“Drivers are crossing over the centerlines in long curves, and they are trying to pass in [the] limited number of passing lanes we have here,” he says. “Those moves suggest to me the drivers aren’t familiar with the risks of driving on two-lane roads. There’s very little room for error around here – and in the mountains.

“I’d like to believe that carriers would pair new drivers with experienced drivers to ease them into these advanced driving situations,” he adds. “But every winter we see plenty of evidence that suggests otherwise.”

How do flat-landers teach mountain driving?

Aside from the question of whether or not advanced driving skills can or should be taught in an entry-level program, there’s the problem of geography. You can’t do much more than lecture trainees about mountain driving in much of Canada. The requisite terrain simply doesn’t exist.

Andy Roberts owns and operates a driving school called Mountain Transport Institute in Castlegar, B.C., which is located in the Kootenays in the southeastern part of the province.

It’s quite literally surrounded by mountains. MTI offers tractor-trailer driving instruction on several levels from a four-week entry-level course to an eight-week advanced course. It also offers a week-long mountain driving program that includes four hours of classroom instruction, two hours of shifting in a simulator, and 24 hours of in-truck instruction on any of the four mountain passes located near the school.

Perhaps surprisingly, even B.C. does not include any formal mountain driving training in its existing CDL training or testing.

Roberts says the B.C. driver’s handbook contains a couple of pages of decent information on the topic, but drivers are not necessarily tested on the material, and there’s no mountain component to the driving test in a province with more mountains than anywhere else in Canada.

“My entry-level program includes at least one trip down a mountain grade, and my advanced students get two days out there,” Roberts says. “It’s not ideal, but at least the entry-level driver gets some exposure to the driving techniques required to drive safely in the mountains.”

Facing mountains the first time

Drivers exposed to mountains for the first time face a dilemma. They often don’t know what lays ahead, and therefore won’t be aware of what speed they should be traveling.

Some grades have signs that display a profile of the hill; some signage offers ambiguous warnings like, “Use Lower Gear” or “Slow Down”. But lower than what, or how slow?

An Arizona company completed a six-month trial of a technology designed to provide drivers guidance and warnings about the proper speeds to use on slopes and curves. Research indicated drivers were operating perilously close to the rollover thresholds of their trucks, and operating much faster on hills than proper mountain driving techniques would suggest.

“All drivers were running very close to the tip-over threshold on the curves.”

– Garth Lawrence, Road-Aware Safety Systems

Road-Aware Safety Systems combines detailed GPS maps and accurate three-dimensional road geometry with known values on vehicle dynamics (truck configuration and load center of gravity, etc.) to determine safe travel speeds.

“Our data showed all drivers were running very close to the tip-over threshold on the curves, and well above ‘engine brake-only’ speeds on the slopes,” says Garth Lawrence, the company’s managing director. “After we briefed the drivers on the risks of excessive speed they did slow down in the curves, but they continued to drive faster than the recommended speed on the hills.”

Recommended speed in this case was calculated by the Road-Aware application, and was based on the weight of the load, the steepness of the slope, and the engine’s retarding power. Drivers were urged to descend the grades using engine braking only, saving the service brakes for possible emergency stops.

“In about half of the slope runs, drivers reduced their speed by using brake snubbing to slow the truck, but did not get down to the recommended safe descent speed,” says Lawrence.

“Many times, we saw drivers running 20 mph or more over the recommended safe descent speed, driving right past a runaway truck ramp that the Arizona DOT says is used about twice a week by runaway trucks. For some reason, drivers seem more willing to accept ‘advice’ regarding speed in curves, but they are much more cavalier about slopes.”

The problem, Lawrence says, is that drivers are not provided an accurate recommended safe speed based on location, road geometry and vehicle dynamics.

“The signs say, ‘slow down’, but not to what speed.”

Safe mountain descents

According to Roberts, drivers should come down a grade using only the engine brake to maintain the descent speed. He says drivers should not need to use the service brakes to slow the truck if they are driving at the appropriate speed.

The engine brake provides the most retarding power at a higher rpm, so keep the engine speed in the 1,800- to 2,000-rpm range. If this slows the truck too much, use Position 1 or 2 on the engine brake rather than upshifting to a higher gear.

“If you need a service brake application to check the speed, you’re in too high a gear,” he says. “Conversely, if you are running the engine brake at 1,500 to 1,600 rpm on Position 3, you’re in too low a gear.

“The steepness of the grade will vary, so toggle the engine brake between the three positions to maintain a safe, steady speed,” says Roberts. “Use Position 3 on the steeper portions, and toggle back to Position 2 or 1 on the less-steep portions of the hill. If you’re in the right gear you should not need to apply the service brakes to slow the truck.”

About engine speeds

In recent years, much emphasis has been placed on keeping engine speeds as low as possible to conserve fuel, so 1,800-2,000 rpm may be forbidden territory for some drivers. You are not using any fuel when using the engine brake (no more than you would at idle).

With the engine brake on, the engine is acting like a big air compressor that’s driven by the momentum of the truck via the drive wheels. Keep the engine speed high, and don’t worry about fuel economy.

Some automated transmissions are programmed to upshift automatically when engine speed reaches a certain point. While running the engine at 1,800-2,000 rpm, you may need to place the transmission in “manual” or “hold” mode to prevent an upshift. If you are going too fast to begin with, even at high rpm, the weight and speed of the truck – coupled with the steepness of the grade – may eventually cause the transmission to upshift to protect the engine from overspeeding.

Obviously, the problem there is not an inadequate engine brake. It’s that the truck is going too fast for the engine brake to maintain a safe speed.

“If you get into the wrong gear, the time to fix that is at the top of the hill before the brakes get too hot,” adds Roberts.

Drivers were once told to “use the same gear to come down the hill that you used when climbing the hill”. But that doesn’t always apply today.

“Engines are more powerful than they once were and may be capable of climbing faster than they can safely be driven down the hill,” Roberts says. “Besides, you may have a different load on coming down than when you went up the hill, or you may have never been on that hill before.”

The best course of action is still to choose a gear that will allow the truck to maintain a speed where the engine rpm is in the 1,800- to 2,000-rpm range in any of the three engine brake positions, depending on the steepness of the grade.

What about disc brakes?

All the technical detail we have discussed here, so far, relates to drum brakes.

Drum brakes are subject to brake fade because excessive heat can change the lining’s friction properties, and the drum expands as it gets hotter. Disc brakes are fundamentally different in that the rotor, which rotates between two brake pads, expands toward the friction material as

it gets hotter, shortening the application stroke and actually improving brake performance.

If the tractor has discs and the trailer has drums, or vice versa, an imbalance situation could result where the disc-equipped vehicle is doing more of the work, causing the brakes to wear faster.

However, even with disc brakes, the weight and speed considerations still apply. A loaded truck barreling down a hill will need a longer distance to stop than when it’s operating on level ground.

If you stick with Roberts’ advice on how to descend a mount grade, it won’t matter if you have discs or drums because you won’t be using any brake on the hill anyway, right?

(Photo: istock)

5 tips to descending a mountain grade

  1. Make sure your brakes are properly adjusted and in good working order before venturing into mountainous terrain.
  2. Slow way down or stop in a brake check area at the top of the hill while the brakes are still cool.
  3. Proceed down the hill in a gear that allows the truck to maintain a speed where the engine rpm is in the 1,800- to 2,000-rpm range in any of the three engine brake positions, depending on the steepness of the grade – and without making a service-brake application.
  4. Avoid the temptation to upshift if you are seemingly going too slow. Use the engine brake to control vehicle speed. The grade might get steeper around the next curve.
  5. Ignore the speed other drivers are doing. They may be lightly loaded, inexperienced, or driving dangerously fast for conditions.

This article originally appeared in the July 2019 edition of Today’s Trucking.

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Jim Park was a CDL driver and owner-operator from 1978 until 1998, when he began his second career as a trucking journalist. During that career transition, he hosted an overnight radio show on a Hamilton, Ontario radio station and later went on to anchor the trucking news in SiriusXM's Road Dog Trucking channel. Jim is a regular contributor to Today's Trucking and, and produces Focus On and On the Spot test drive videos.

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  • I just wanted to say what a well written article. Thank you. I’ve year’s of experience but none in the mountains, until recently. I’m one of those drivers that relies heavily on that engine brakes but haven’t run them up to 1800 to 2000 rpm that just seemed way to high. I’ve just started running an automatic because my wife got her licence and is running with me and wanted the automatic. We’re in a 21 model truck and getting used to how to run it. The truck manual says to run at what your writing. Your article gave us some clarification. Thanks

  • My employer sent 4 of us to MTI for the mountain driving course… at that point in my career I was 27 years in… the knowledge I gained at MTI was incredible… today I drove southbound over and down Douglas Pass in western Colorado… zero brake use… all controlled by gear selection and engine brake application that I learned at MTI. Andy and his crew of instructors are probably saving lives… and reducing truck related crashes on mountains.

    Thank you Andy & MTI crew!

  • Yup – Yup and Yup! again.
    This inadequate level of training starts before they’re even in the truck.
    It starts with the Air brake Endorsement – and YES I am talking about Brampton – Mississauga.
    Just last week on Friday – I have first hand knowledge from a new student about their experience.

    He wanted to enrol with us at Tri-County but we are currently booking into June – so he decided to go to another “school” in Kitchener.
    So from him – not hear say – first day in the truck – WITH ANOTHER STUDENT (not supposed to be happening during COVID) – first day – they are at a red light and asked by the owner/instructor to change seats!!!

    My main point is this – Mountain driving starts with Air Brake System training – in this students case he was sent to Mississauga (OSL certified Signing Authority) $200 – watched some videos and presented with the Z Endorsement.

    He has come back to us – quite astonished with his experience – has preceded with formal complaint and is waiting for June, because he wants to be a safe driver with quality training behind him.

    His words – ” I have my Z, but I don’t know anything!”

    It is critical at this stage for SA’s to teach more than just the minimum in an Air Brake course – there is plenty of time over the two days – For example how lighter brake applications only work a couple of brakes – thus over heating.
    How it is important to learn how to shift an automatic – as your article describes – how to properly use the engine brakes – proper use of cruise control setting – often many hills can be descended safely by lowering the cruise setting 5km/h or so and the engine brakes come on automatically – did this recently in a 2018 and 2019 Feightliner in the Appalachians and it worked great – hardly drove with my feet – just input on the steering wheel controls and occasionally an increased setting on the engine brake.

    Perhaps we do need graduated licensing for commercial vehicles as well. – or include a mountain/hills component for MELT.
    The various Ministries of Transport have to be involved and require much higher levels of training by approved schools only – MELT has proven not be good enough.

    I fear every day reading the headlines – the next Humboldt tragedy is only a matter of time – it is going to happen again.

  • Great article! Thanks for touching this subject. Perhaps with escalating insurance costs and the demand from both carriers and their insurance providers that drivers have pristine driving records more must be done to train new drivers how to handle mountains especially in winter. Reading this just substantiates why so many insurance providers are no longer willing to underwrite policies for large trucks.

  • While I do not know the percentage of drivers with a working knowledge of the air brake systems they use daily, it amazes me the number that don’t know. I have spent the last twenty years in the towing and recovery industry and the number of drivers that do not understand their trucks are truly astounding. No one expects a driver to know the details of how to design or rebuild a truck or in fact know how to tow one, but, they should have some working knowledge of its functions.
    The case in point here is the number of drivers, and some of them with many years behind the wheel, that have offered to release the parking brakes as I picked up the rear of their truck to tow it. For some it was a minor slip fuelled with a little enthusiasm but most had no idea of the system. For those that missed it on their last walk around, there are no spring brakes on the steer axle. This is to allow for continued rolling friction of the steer tires even in the event of the air system failure.
    While this may not seem like a big deal, it is an indicator of a lack of the lack of knowledge and/or training.
    Just my opinion

  • The disclaimer of a nearly 2 year old article should be at the beginning. Any advances in technology may make some of the points out of date.

    Road signs, engine wheel brake advances etc…

    • Joseph,
      The date of the article is irrelevant. The information is as current as the ‘best before’ date on your loaf of bread.
      Mr. Park has covered all the bases on ‘Mountaineering’.
      The biggest problem is, and always has been, the trucking companies turning new drivers loose without a mentor or proper training.
      Twenty nine years ago, (with already 20 years experience), I worked for an infamous carrier from Salmon Arm B.C. They wouldn’t let me go through the mountains until I ran double with another driver for a week and ‘shadowed’ for another week. That was an eye opener and steep learning curve even then.
      Today I am responsible for a small fleet and we hire only experienced drivers and regardless of where they came from we spend at least 1 week training in the mountains with every driver. There are often many drivers who don’t make it
      through the training program.
      The rules of engagement have not changed since 2019 or since 1992 or even before then. You can come down a mountain too slow a thousand times, but only once you may come down too fast.

  • For most of the last 30 years I have to shake my head. We did not have engine brakes when I started in the 70’s. General rule was dropping a grade you never got more than 1 gear higher than you came up with.
    Now with engine brakes I see a lot of guys using brakes on a downgrade, staking their life and the lives of others on a 14 gauge piece of wire, that’s pretty risky if your brakes are already heated up when the jake quits.
    Keep it down to where you actually can stop when your jake quits.

  • I overlooked this article for a few weeks because I thought I knew all I needed to know about driving in the mountains and because, being retired at this time, it’s unlikely that I’ll go over them again. I had much experience in the Appalachians over the years, driving out of Ontario, but I changed jobs at one point after about 40 years in the saddle. The new company asked me if I was willing to cross the Rockies, which I had done, but only across I-80 and I-40. I told them I wanted to cross the Rockies, but since it was early Fall, I told them I would cross the following winter, but I wanted to wait until spring. So in mid-spring they dispatched me and I ran the mountains precisely the way Jim Park advised. I can’t remember if I was told how to do it or it was just common sense, but at any rate it worked well for my last few years behind the wheel’