I do not want to hijack this thread, but am going to put up some information that people operating RV's with air brakes really need to pay attention to.
Failing to know your braking system will get you into deep deep trouble.
And it is YOUR responsibility to know.
You have heard the news reports of the truck that lost it's brakes...it didn't 'loose' them, they either were not propely adjusted, over-heated, or the driver ran out of air. And when that happens, things get worse from that moment on.
The driver needs to know about what to look for when you start the engine..the air gauge does certain things and you need to know what those things are and what they mean. And it will tell you when you are about to have a really bad day. But you need to know how all that comes to be.
This is a YouTube course using a simple presentation.
http://youtu.be/_gmoIkP8ywIGary Haupt