2015 Seneca Exhaust Brake

[Life on the Verge]

When do you use the exhaust brake? When should this switch be turned on or left on?

[RVermont]

I use it when in heavy traffic that is speeding up and down frequently. Just pull foot off throttle and it slows down with less braking. Keep in mind that you want to let people know you are slowing so use of brakes and brake lights can be a good idea .

And of course I use it in mountains to save on braking, however on normal rolling hills I tend to turn it off as I want to build some speed to set up for the next hill climb.

I find that I leave it on quite a lot. I do pay attention to signs prohibiting its use.

One thing to remember is that it stops working at 15mph. So when slowing you need to be ready to increase brake pressure when it shuts off. Especially important in heavy traffic as it shuts off and unit will free wheel. Practice a few stops to get used to the effect.

[Robbbyr]

My exhaust brake switch is left on probably 95% of the time. I only shut it off when I see the signs prohibiting its use, and sometimes in the hills where I consciously want more downhill speed like RVermont mentioned. With experience you can learn just the slightest pressure on the throttle will keep the exhaust brake from actuating, yet not cause the engine to accelerate. That's another way to "coast" without flipping the switch off. At least mine works that way!

[rgolding]

Ours is on all the time, where allowed. I turn off, if I see signage, but its right back on as soon as I'm out of the area.

[McGintys924]

I also find that I leave mine on most of the time (rarely do I see signs out east). From my understanding this is changing the direction of the blades in the turbocharger and gears in transmission. I definitely find that it helps on the hills and have learned how to apply just enough pressure to the accelerator to disable the feature without increasing engine output on hills with flat sections (Paul, like the one on 77 in Virginia just before NC when you travel down there).

I find it invaluable when you are preparing to exit the highway and the downshift points are specifically control by speed and predictable. As was mentioned you do have to be ready for it to go from a persistent decrease in speed to no help whatsoever at the 15 mph mark.

I even find I let it on in the background of the cruise control. Although cruise control does deactivate the exhaust break, deactivation of cruise control activates the exhaust break.

I have no idea what breaks will cost us (anyone been there yet?) but imagine it’s expensive and want them to last as long as possible.

[Rustynuts]

For me it depends on the type of road and conditions. I find it annoying some times when it activate when I dont want it so have it turned off on most freeway driving...its pretty easy to just flip it on when needed like approaching an off ramp. Most exhaust brake systems turn of the brake lights when activated which does on my Seneca so there is no need to press the brake pedal to activate the brake lights, I realized this when going down steep grades at night, I could see them in the trailer. If you read the signs in most states about exhaust brake use, it says "un-muffled" use and on the Senecas the exhaust brake is muffles as it still just runs through the exhaust system unike it does on a lot of Semi trucks as our systems are done through the variable geometry turbo (VGT) which uses a plate with vanes.