Keeping RPM's down on downgrade

I'd like to caution you new guys against relying on your jake. In fact until you learn how to drive in all terrain and weather, you should turn it off and forget you have a jake.

A Jake is controlled by electric solenoids. Those solenoids get their signal to activate by a little tiny 12 gauge wire that runs from from the engine to the trucks harness to the ecm and up into the cab and finally to the dash switch. Lots of places for connections to become corroded, loose, runbed through, shorted out, etc. plus they require proper adjustment to be effective. Do you really want to be doing fifty, heavily loaded, down a bad mountain grade when Murphy decides its time for the jake to shut off?


There are bold truckers, and there are old truckers. There are no bold and old truckers.

 

I run out in the oilfield in eastern utah and western colorado, along with all the previous mentioned hills, like vail, rabbit ears, etc... I approach all of them the same, if they're slippery I get in a low enough gear my jake will hold me back on the lowest setting. If really nasty I'll throw a set (one on each axel on apposited sides, 2 total) on top of both drive axels and a steer. It's all about learning to feel the truck, there are points when I will turn the jake off (usually just by applying just enough pressure to the throttle to cut it out) and let the engine do all the work, because the lowest setting is causing my wheels to lock up. I shoot for lower rpms, just in case I have to pin it to straighten myself out. But if your truck is equipped with a johnny bar, the trailer brakes will do the same thing. I have and 08 550 Isx15 and it red lines at 2100, most of the time I drive her from 1300 to 1650, letting her wind out only when the extra jake power is needed.
It scares the hell out of me that the megas will send a wet behind the ears driver across country without any knowledge of how to properly decend steep mountain grades. The other day while headed up the switchbacks on 191 north of vernal utah, I had a swift driver push me clear off the inside of the turn we were both navigating. As I came through the turn, her trailer over halfway through my lane. I grabbed the radio and chastised her for not paying attention to her trailer and continued on my way up. She responded that she had only been on her own for two weeks and she was scared ####less. I said "only two weeks? What the #### are you doing up here?" She was white as a ghost when she finally got down into town, a driver I knew rolled past her while she was waiting to turn. Go slow. It only takes once to kill yourself or someone else. Good luck

 

They try to train em the best they can without getting fired. Case in point, during my Swift days was sitting in the terminal talking to a mentor, he had been called in by Safety to answer why he had reached over to turn off the jakes from the jump/trainer seat. His female student had refused to turn it off is why he did it, and the lesson was how to get down the grade without jake brakes. She threw an absolute hissy fit and they were immediately routed back to a terminal so he could be 're-trained' as a mentor. SMH

 

That hill from vernal to price is wicked.

 

Sounds like the op needs some more downhill driving with a full load....nothing better than having to fly down with no brakes to teach you to slow down in the future.

My simple rule is maintain control at what ever speed is required. No load is worth running wild and losing it on a curve.

 

+1 on the little wire and solonoids. I was screaming the jakes going down at 60-ish one time and then I hit a NY pot hole and the jolt shut my jakes off. Before I knew it, I had a ticket for 72 in a 55.

Hills were around before jake was. Cresting the hill slow saves alot of pucker.

 

Yeah, I believe so. I heard that they don't allow you a jake or cruise for your first 6 months or something.

 

Clessie Cummins developed the compression brake after nearly crashing on old Rt 66 coming down Cajon pass back in the 1930's.

He worked on the idea and finally made it happen in the 1950s. First test engine was a 1950's N block Cummins. The test driver was a skeptical old crusty trucker who was immediately sold on the invention the first time he tried it.

Can you believe that the money counters at Cummins REJECTED investing in their founders idea because they didn't see any value in it?

Through an in law Clessie got in contact with Jacobs Manufacturing and the rest is history.