Jacobs brakes are used to slow the engine of a diesel tractor trailer loaded with logs, or rock, or cattle when it needs to be slowed without using the air brakes, which require a precious commodity that can run out at harrowing times and leave a truck spinning its wheels.
Known as engine retarders, or just Jakes, the compression brakes were developed commercially in 1961 by Clessie Cummins of Jacobs Vehicle Systems.
They are used extensively in places like the North Idaho backwoods, with its switchback roads and steep grades, where bunks filled with timber are hauled to the low country — instead of using a flume, or trucks with water-cooled brakes, or any other brake system subject to fail under duress.
Jake brakes have your back.
For many truckers cresting a hill unforeseen, or anticipating a comfortable descent, the Jake is the pixie dust that keeps them safe.
A guy from Oregon — who long hauled for a while as a young man, before he carried a hamburger belly and gruffed on the steel seat of a D8 — remembers coming down the Columbia River grade near Vantage. He was fully loaded and hitting the Jake, letting the slow, smooth sojourn coddle him graciously to safety over the long highway bridge before heading up the other side.
Jakes are like that. They got your back.
A friend of mine first explained the origins of the brake to me in the woods of a logging show we worked. He was a rigging slinger who had tried his hand at driving truck — mechanic-ing on the fly, he called it — and learned about retarding systems from the greasy, duck-billed man who kept our equipment running.
“It’s called a Jacobs brake,” he said, and I took his word for it.
It’s been years since I was in the jaybird seat behind the engine of a rig that had one. But I remember still flipping the switch, the other hand on the wheel as the loaded Kenworth growled its operatic bass down a cliff-hanger road, like a big cat being scratched.
In rural North Idaho, Jake brakes are what’s left of work, and even here, our cities are moving out of town.
For those who know their calming effect, it’s hard to take seriously people who complain about the Jake.
I lived many years on a dusty backroad where the logging on the hills behind my house kept the deer and elk in feed.
When the trucks came down in the black, early morning rain of October, their Jakes rumbling through the wooded swales, it roused me from my sleep. Just in time.
If it wasn’t that, the solemnic clanking of trailer chains lulled those last dreams before the bubble of the coffee maker and feet hit the cold floor.
Anyone who has worked in the timber industry — with its tattered clothes, re-prod, pumpkin patches and sawdust dreams — welcomes the song of the Jake. It smells like wood and floury road dust that squeaks under the soles of your boots.
It is the sound of industry, a tax base, money for schools and roads.
We don’t talk like that much anymore, because we’re almost through a quarter of the 21st century and income is mostly derived behind closed doors.
The Jake brake, however, is still a part of the North Idaho backwoods and back roads. And truckers are glad for that. They know that the Jake has their back.
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Ralph Bartholdt can be reached at firstname.lastname@example.org.