Jakes - Coquihalla Highway

Speaking of RPM, some of you would remember when the scale at Golden was at the bottom of Kicking Horse on your way into town from the east? I was in there one snowy morning while the inspector was taking a huge chew of my butt for my transgressions (which were many as I recall), when all of a sudden came a huge howl outta the east. It was getting louder and louder when all of a sudden the scaleman (who was about 5'4" tall and close to the same width) jumps up from the desk, hops around the counter and yells "LETS GET OUTTA HERE NOW!!!"

So we did. I've no clue how this guy made it around the twisty bits before the last downgrade into town, but emitting a howl akin to a V12 Ferrari, here comes this daycab Mack running about 50MPH or so with a tandem flatbed and a couple of bundles of flatbar onboard. Smoke off the drives, smoke and flame off the trailer bogies, and if I had to guess @ the RPM he was turning I would say high 4's as I lost the accuator valves on an ISX a couple of years ago at the Pete dealer at Laughing Louie and we pegged 3400RPM on the laptop before we got it shut down and the howl it made was nothing like this old Maxidyne.

So instead of cleaning out the scalehouse the guy went straight thru town, the scaleman told me to go get my paperwork and get gone as he had more important things to do, and he set off in hot pursuit. I never did catch the name of the guy with the Mack so I could thank him though.

 

Lmao that's awesome!

 

My current truck is a DD15, good jaking power. Same as yours my brake lights come on in 3rd stage.

 

Do you get drivers following you down long hills telling you you're gonna burn up your brakes?

 

I would if I turned my radio on.

 

I would check the switch it might be in position 3 but only giving you first stage

 

There's always 'The Fred Flintstone' :

 

I pulled super b's in BC for years with a Cat engine and it was common to have to drop into the bottom end on the 6-8 % grades unless you wanted to burn up your brakes, The guys who are going down faster without using their brakes have both an engine and driveline brake likely. I had a friend who got pulled over at the bottom of Kamloops hill once with a full load of lumber because the cop thought his brake lights weren't working.

 

Back when the toll booths were still on the coqu, I came out of the brake check area at the top of the hill one night, and a driver for a carrier which shall remain un-named, flew by pulling a tridem container with squooshy tires. Before I could pick up the mike and say something to him, he was passing the truck in front of me, and that driver was already on the mike telling him he better get some speed out of it NOW.
By the time I hit the snow shed, the smell of burning brakes was pretty strong. Lucky for that guy, the grade levels out quite a bit after you clear the snow shed, and he did manage to get it stopped in the pull off area at the bottom.
When I went by, he was out of the truck which was just barely visible in a cloud of smoke.
I hope that was a teachable moment for him.

 

I've run the "coq" with tridems, Super Bs and 5 axles for decades. This is my take on it.

The Coquahalla, especially "the smasher" AKA snowshed hill, is a little strange to get used to. Basically you've got 8% until you get in the shed and then about 6% or less until the just before the Shiloh bridge where it gets steep again for a bit but levels off on the bridge.

5 south into Merritt is similar in that there is a fair bit of wind when heading south and that helps:

All that to say, that the likely reason Super Bs are passing you is because they know where the steep parts are AND they get to a speed where there is so much wind resistance that they reach an equilibrium where they won't gain any more speed with the weight they have, aerodynamic drag being created and what the engine brake is able to hold.


Air resistance squares as speed increases.
The aerodynamic drag at 50 MPH is 4 times greater than at 25 MPH.
You come out of the snowshed an it's always a wind tunnel, add some speed and you might as well throw out a parachute. AIR BRAKES!

On 5a where it's 10%, you can't do that because it's not very long, it's in a canyon and there isn't much wind to begin with. Same with hills on hwy 3. Too steep with hairpins at the bottom.

The conector into west bank has a little more lea way.