Exhaust or jake brake or neither?

You should be able to hear the jake or exhaust brake when you decelerate. Other than that, check your manuals.

Tell us what engine you have-- that MAY give an answer.

If not, easy to describe what an exhaust brake looks like and where to find it.

And there is usually a switch to activate it........

Your other post said you had an engine brake???

An 'engine brake' is on the engine and controls exhaust valves opening them.....when engaged you will hear a loud pop-pop-pop sound (just like the semis)

An 'exhaust brake' is mounted in the exhaust system and closes it own control valve to create back pressure in exhaust system (back towards engine).....when engaged you will hear an increased exhaust hiss

Both types of brakes have to be turned on........usually a button on dash.

OP: When we purchased unfortunately it came with no manuals. I did find the original sticker from the window however, it says, Cummins ISC 8.3 350hp Diesel engine. It also says exhaust PAC brake (?). The brake pedal says air brake on it.

The only button I can find on the rig in the driver section says engine brake.

So if this it, how do we use it?

Thank you so much for your help.

Old-Biscuit wrote:
An 'engine brake' is on the engine and controls exhaust valves opening them.....when engaged you will hear a loud pop-pop-pop sound (just like the semis)

IMO this is a bit misleading because most MH's have a muffler on their engine brakes, (aka Jake Brakes) and are pretty quiet. Any pop pop noise is hardly discernable.

Jacobs Company also makes an exhaust brake so both are sometimes called Jake Brakes. If you have an exhaust brake - just call it a Pac brake and no one will be confused.

The "Pac brake" is an exhaust brake and a good one at that. Congrats!

Yup, both the engine (Cummins C) and PacBrake tell you that you have an EXHAUST BRAKE.

Which also means you should lube the brake: http://www.pacbrake.com/index.php?page=maintenance-4

Well since no one told you----if it is working properly, you turn it on, remove your foot from the accelerator, and you will feel it not only slow down but shift down.....Thats basically how it works. When it is turned off only your vehicle brakes slow you down when applied.

To use the exhaust brake......turn it on
When you let off the accelerator pedal it will engage (closes...has some method of regulating exhaust back pressure) and you will decelerate. Your Allison transmission will probably downshift also slowing you even more.

When you push on accelerator pedal the exhaust brake will disengage (open) until you let off pedal again.

Great for downhill as it will help slow/control downhill speed.

Turn it ON when you want to use it....turn it OFF when you don't

I use mine whenever towing
I even use it sometimes when not towing
Simple.......push the button

Try it out...see how it works.