Air leak?

Absolutely right on target! DOT cops can hear air leaking sometimes just sitting on the side of the road as you pass by. More then one driver has been stopped after passing a scale and an officer hears air. If you are stopped for an air leak you are OOS until that air leak is fixed. Get that air leak fixed ASAP! next time you are in safety ask them what happens when a driver is placed OOS because of a mechanical issue! If you do have an air leak ONLY operate as short as you can to get to a shop, OR better stay put and get a mechanic out to your location. Glad hands are notorious for leaking around those seals. Keep a few in your truck. When I was active, part of my pretrip after picking up another trailer after a drop and hook was to charge the trailer's air system and shut my engine off and walk around listening for air leaks. I paid particular attention to airbags. Those dang things have a tendency to dry rot. I once picked up a trailer at a place in Georgia that had sat so long there that the company lost track of it. As soon as I charged the airlines I blew an airbag. Just as pain tells you something is wrong with your body, air leaking tells you something is wrong with your truck.

 

If it’s only while turning it’s most likely @ the glad hands. Also it could be a crack/leak in the line itself. Do you have enough slack in the lines? I once went to the dealership for service, and they had wrapped the lines around the pogo stick and the next sharp turn I took snapped e-line and locked the brakes.

Be careful, if your air is dropping that low it can be more than an OOS. You can have an accident. It’s dangerous. Don’t be upset with these guys for being slightly irritated that you provided such little information. It’s a serious issue.

 

I am betting it is at least slowly leaking even when you are straight, just not audible.
If it is not a gladhand rubber(you should always keep extras in the truck anyway), I am betting either a crack on either the line real close to where it hooks to the tractor, or close to the gladhand on the trailer end, and the crack opens up when you turn. \If it leaks when you are not using the brakes it will be on the emergency line (red), and if it only leaks when you are applying brakes, the service line (blue).