jake brakes; when to use them, when not to

I use my Jake pretty much all the time. Any time I can save my service brakes, (you know, the ones that are expendible and will eventually have to be replaced based on the frequency that they are used) I'm all for it. Although, there are times I dont use them.....truckstops, rest areas, under a certain speed, ect, ect. Not because they are loud and obnoxious, which they arent, just because thats when I feel they arent necessary. But, I dont limit the use of them strictly for put-puttin down steep inclines.

As far as my excessive jake usage goes, you'll probly never know Im using mine because they are exceptionally quiet. Yeah, in a way, I wish they were louder, but if they were, Id be attracting the law all the time and would have to limit my use and I dont wanna do that.

And no, I dont use them for shifting. Maybe its just me, but I never could figure out how to do that eficiently without adding difficulty.

I dont use them on icy roads, but I do use them even when its raining. Not when bobtailing of course, or pullin an empty wagon but if Im loaded and have the drives almost maxed out, I find it hard to believe that the jakes are strong enough to cause a jackknife. I dunno, maybe thats just me.

 

Since I was running heavy almost all the time, 85k-100k, I was in the habit of using them on the freeway. To me, they gave me just an extra little bit of breaking if I needed them. Of course I wouldn't use them in TS or rest areas (unless I forgot or bumped them). My favorite trucks had 2 switches for jakes, 2 cyl and 4 cyl and turn both on for full jakes. Most of them just had a Hi/Low setting.

 

It might put a little extra wear on the face of the throwout bearing, that is, if you're stepping on it hard enough.

I do the same thing--lightly rest my foot on the clutch pedal to keep the jake from coming on while I shift. I don't think it's hard enough to even contact the pressure plate though. It only takes a very minute amount of travel before the jake switch cuts out.

 

if you dont know how to slip shift w/o touching the clutch with the jake on then turn the jake off.. i hardly turn the jake off.. i have been doin it for years you just have to learn the accelerator and know how far to take your foot ff the pedal so the jake doesnt engage and the rpm drop so u can slip it in gear. you will eventually wear or break ur drvln if u do it enough tym's i shut it off just in small towns and truck stops. my preference and thats what its all about is preference ....

 

The first few minutes of a rainstorm, the water is mixing with the oil/rubber/crud on the road and makes a very effective lubricant. Its a good time to be cautious with a jake or service brakes. Once the road gets good and wet, that stuff gets diluted and washed away.

Any time there is standing water on a road surface, you're at risk for hydroplaning. So, you start sliding around with a layer of water between the tires and the road... take your foot off of the throttle - but Mr. Jake kicks in. You're starting to jackknife.

Jakes are good for controlling your speed down any descent, and when coming off of the highway onto an exit ramp they'll help slow you without wearing out your service breaks prematurely.

Definitely don't be using them on snow covered or icy roads. In the winter the highway surface may be fine, but any of the less travelled portions of the road (exit ramps, turn lanes, etc) may have enough ice on them to start you into a jackknife when the jakes kick on.

If you gear down enough, you can descend any grade against the transmission and the jakes. In another thread, someone mentioned selecting a gear for descending without a jake as being top gear no. minus the grade percentage: 10-speed, 6%... 10 - 6 = 4, use 4th gear. On a snow packed surface, coming down a grade very geared down - do it without the jakes.

 

You are correct. Any driver who has ever driven in the mountains where the roads are covered in snow or ice knows this. My trainer never mentioned it to me when I was in training, and I nearly ended up in a ditch because of the jakes being on. If it is dry pavement and you are fully loaded going downhill, then by all means leave them on. If, however, you must travel through the snow or ice, turn them OFF or face the consequences.

 

Well thats not Swift hating, but then if your were even a driver you might know the difference. But your not so you can not.

 

If you are using your clutch correctly to shift with the clutch, not floating you should only slightly out pressure on the pedal, so if your touching the pedal enough to assist you in shifting then your not floating. Its actually a good thing.

And by the way changing out brake shoes is not a monumental task and I seriously doubt that using your jake in stop and go traffic or around town is saving your shoes by much, maybe some but very little.

It would be great if they would include some shop time while teaching drivers about the trucks it would open peoples eyes dramatically. As to the wear and tear question, it cause wear on the throw out bearing, the bearing arm and the fingers on the pressure plate, but not the clutch plate itself. The biggest problems to floating if done incorrrectly is to the internal transmission, u-joints, ring and pinion in the rear end.

 

When i went to get my cdl at NECC, we went to their truck shop to see a cut-out of the engine,transmission & brakes. Very good information