I am new here and not sure where to post this so if it is in the wrong place any mod can move it. It has come to my attention that many people who are driving the MaxxForce with the 11 or 13 and have the engine brakes do not understand how they really work consequently they are not working correctly for them so they think they are junk when they are not.
Here is how the three position switch works.

Engine Break Switch positions:

Switch Position 1
This is called the “Latched.” This position activates when the foot is removed from the accelerator.

Switch Position 2
This is called “Latched with service break.” This position activates when the service break is pressed and deactivates with clutch or accelerator.

Switch Position 3
This position is called “Coast.” This position activates when the service break is pressed and deactivates when the break is released.

The engine break works best between 1900 and 2100 RPM