We live near and often travel several long grades where brake fires are common. Most check at the top to be sure the auto adjusters have not run them up to much as some times one will be hot before heading down the 6-8 mile 6+% grades. They also check the tires. However the brake check areas are really left overs from a few years back when Brakes were not as good as now. But the drivers that do not understand long grades and gears and try to use the bakes on the long grades are still with us... We see several trucks and RV's with brakes smoking or flames most every trip over the passes. Most of the trucks can put the brake fires out. The RV's usaly do not fair as well.. Our grades also have escape roads. Roads with about 16-18 inchs gravel that just lets them sink in and will stop them. Then they have to have wreckers pull them out. Also common.
We spent most of our money traveling... Just wasted the rest..
Trucks that stop (maybe 5% or less) do a brake inspection and let the brakes cool off. The trick is use a lower gear as well as the jake brake and then trucks still have to use significant braking. 80,000 lbs is alot to hold back. I've seen many runaway ramps with tire tracks in them.
I find on my own rig that I can just drop down to second gear, take my foot off the go pedal and let engine braking and gravity do the work, while I'm maintaining a 55-60 mph speed. To me it's 4 miles of downhill fun.
but it doesn't work in a semi-truck.
The weight is simply too much, you can actually over-speed the engine thru the mechanical forces working on it.
Diesel engines don't engine brake like gas engines do, that's why they invented engine brakes ( Jake Brakes is the common one) which forces engine back pressure. You can still over-speed it even with the engine brakes full on if you are heavy enough (or the brake is weak enough).
Comparing a pickup truck with a trailer to even an empty semi-truck is silly. Until you drive a semi, you simply cannot understand the forces working on it. The weight is overwhelming. Even a unloaded light semi and trailer weighs more than your entire rig. Then they add another 50,000 pounds of weight.
Never tried to compare them. By the way, my father drove long haul trucks all his life, along with managing a truck terminal. One thing he did show me when I rode along as a kid was the way to properly go down a grade, using the truck's gearing and using the brakes only when necessary. That is how I can spot the pros from the not so pros. Done right, you should arrive at the bottom of the grade in one piece and with your brakes not producing smoke and stink. You will also notice by my signature that my pickup is diesel powered.
Richard L. Ray
SSgt USAF (Retired) Life Member DAV
W4RLR 146.52 mhz
2005 Ford F-250 Lariat Crew Cab
1995 Jayco Eagle 277RBSS fifth-wheel
"Never ask a man what kind of computer he drives. If it's a Mac, he'll tell you. If not, why embarrass him?" Tom Clancy
Down Monteagle at 55-60? I am not that experienced at driving my coach yet, so I do that grade at about 40 mph in 3rd gear with exhaust brake, then 40 mph coming back up.
You can go too slow a 1000 times
You can only go too fast once.
55-60 sans trailer. 40-45 both up and down with the trailer. Sorry I was not clearer. I'm not in that much of a hurry. As the trucker's bumper stickers used to say "Speed on brother, hell ain't HALF full!"