Forum Discussion

holstein13's avatar
holstein13
Explorer
Aug 08, 2015

Jake brake on or off driving on flats or small hills?

One of the debates we had this week was whether you should drive with your Jake Brakes on or off while on flat land or small hills. Everyone agreed that you should use them in the mountains or steep grades.

But what about hills and flats? The tire and brake instructor said we should not use them because the brakes need a workout to prevent glazing and if you always use the Jake Brakes, you won't automatically adjust your slack adjusters.

The engine guy said that the latest evidence from Cummins suggested that the Jake Brakes helped keep the turbo chargers clean. He recommended leaving it on.

Do any of you have an opinion?
Class A
  • cvbdsl's avatar
    cvbdsl
    Explorer
    Aug 08, 2015
    How about 50/50?
    Not trying to be a smart @** but I find that I do toggle mine off and on depending on traffic and roads/terrain. I definitely like to use just the foot brake in stop and go traffic, for highway I usually set it to use the engine brake.
    I also follow the recommended process for testing brakes and have (not always but often) measured my slack adjusters to ensure that they have the proper travel.

    Chris
  • wolfe10's avatar
    wolfe10
    Explorer
    Aug 08, 2015
    Leaving on either an exhaust or engine compression brake 100% of the time is a good way to not use my favorite gear-- COASTING.

    Particularly in rolling hills, it is much better for MPG to coast down the hill and gain a little speed to attach the next upgrade than to use your brakes going down and then have to go to WOT going up.

    Stop and go traffic or technical driving brings on different priorities.
  • Sprink-Fitter's avatar
    Sprink-Fitter
    Explorer
    Aug 08, 2015
    wolfe10 wrote:
    Leaving on either an exhaust or engine compression brake 100% of the time is a good way to not use my favorite gear-- COASTING.

    Particularly in rolling hills, it is much better for MPG to coast down the hill and gain a little speed to attach the next upgrade than to use your brakes going down and then have to go to WOT going up.

    Stop and go traffic or technical driving brings on different priorities.


    Are you really that cheap that you would actually coast downhill to save gas ?
  • pulsar's avatar
    pulsar
    Explorer
    Aug 08, 2015
    On our previous coach, the computer was reprogrammed so that the exhaust brake came on only if one touched the brake pedal (and the switch was on). The exhaust brake was released when the accelerator was pressed.

    Our current coach is programmed in the usual fashion, but I'll have it reprogrammed next week.

    I also like the coasting gear.

    Tom
  • Mr_Mark1's avatar
    Mr_Mark1
    Explorer
    Aug 08, 2015
    On our previous coach (Dynasty), I used it whenever we started to coast too fast and also to slow down in normal traffic. The cruise would not work if the jake was turned on so I kept it off until I needed it. The Jake would kick off at about 20 mph or so and then you had to use the service brakes.

    We have a 6 speed retarder on the new coach.

    MM.
  • Ozlander's avatar
    Ozlander
    Explorer
    Aug 08, 2015
    Sprink-Fitter wrote:
    wolfe10 wrote:
    Leaving on either an exhaust or engine compression brake 100% of the time is a good way to not use my favorite gear-- COASTING.

    Particularly in rolling hills, it is much better for MPG to coast down the hill and gain a little speed to attach the next upgrade than to use your brakes going down and then have to go to WOT going up.

    Stop and go traffic or technical driving brings on different priorities.


    Are you really that cheap that you would actually cost downhill to save gas ?


    Gee, you can't even coast down a hill without some S*B jumping on you.
  • mowermech's avatar
    mowermech
    Explorer
    Aug 08, 2015
    holstein13 wrote:
    One of the debates we had this week was whether you should drive with your Jake Brakes on or off while on flat land or small hills. Everyone agreed that you should use them in the mountains or steep grades.

    But what about hills and flats? The tire and brake instructor said we should not use them because the brakes need a workout to prevent glazing and if you always use the Jake Brakes, you won't automatically adjust your slack adjusters.

    The engine guy said that the latest evidence from Cummins suggested that the Jake Brakes helped keep the turbo chargers clean. He recommended leaving it on.

    Do any of you have an opinion?


    IMO, neither one of them is correct.
    It is, IMO, purely personal preference. It is YOUR rig, run the engine brake or exhaust brake YOUR way!
    When I had a Dodge CTD 3500, I used to run the the Jacobs Rambrake (an exhaust brake that, according to the Jacobs website, can properly be called a "Jake Brake") ON all the time. Sure, some people said I should not do that, but I ignored them. I liked the way is slowed the truck!
    The choice is yours. Good luck!
  • Ivylog's avatar
    Ivylog
    Explorer III
    Aug 08, 2015
    I like the left foot switch my true Jake Brake uses. Let's me coast and I use it most of the time when I need to slow down.
  • mtrumpet's avatar
    mtrumpet
    Explorer
    Aug 08, 2015
    I have a Jacobs Exhaust Brake on my rig. I leave it on for local driving around town, but turn it off on the highway, especially when using the cruise control. The reason for me is, when the cruise control backs off on the throttle to adjust the speed, it will activate the exhaust brake. I will however turn it on when coming to a toll plaza or Exit ramp. Right or wrong? I don't know for sure, but that method works for me. If steep grade driving, my method may have to vary somewhat I'm sure.

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