This is my first post here, and I don't want to talk (or write as it may be) out of turn, but I hope you have an understanding of your air brake system.
And of the needed air pressure for braking purposes. There is a point where. if your air pressure drops below. the brakes on your coach will lock up...even if underway on the road. If driving and the warning buzzer and brake light on the dash go off you need to as quick as possible move out of the flow of traffic.
Also you should bleed the mositure out of your air tanks every few months or more often depending on your use and location.
