Air Brake pressure drop

[Viva Las Vegas JDR]

I noticed today that when my air pressure reads full (130#), and I step on the brakes about 40 mph, the initial drop in pressure goes from 130# to apprx. 105-110#. It then builds up quickly to 130# again. It seems like a large drop that I didn't notice before...should I be concerned......

any thoughts on the amount of initial air pressure drop after hitting the pedal...I don't know what is considered a normal drop....thanks

[Gary&Terry]

could be your brakes need adjusting, to long a throw on the slack adjusters making more distance to travel thus more air used.

Gary

[77newell]

It is also possible you have an air leak in the braking system. The way to check that is to hold the brake pedal down and see if the pressure continues to drop after the system builds up again from the air compressor getting triggered by the initial drop you noted. Another way to tell is to have someone hold the brake pedal down while you cruise around outside listening for air leaks.

Jon
77 coach