Losing air 5-6 psi per minute while driving

Checked brake chamber and lines with soapy water and sprayer. No leak all of them.

Need to check air dryer and fan clutch.

 

Yes it is auto trans
Tried that with/without applied brake. It doesn’t lose as wildly as while driving.

 

Could the wind be pulling on an air hose and tweaking a glad hand or trailer connection?

 

Thanks i’ll check That too.

It doesn’t fall bellow 100 but compressor is getting overworked

 

some of the auto's use AIR to shift....so check there

 

Yep.

 

i agree with this statement. my truck drops down like this

 

Definatly check the transmission.. My dt12 auto shifts with air and i had a leak in mine, wasnt losing as much air as u were but i notice my air was spitting off more frequently while driving and i put it in the shop and they found a fitting leaking air on tranny. No idea where its at, but the mechanic say its a common problem on the cascadia , but its been good ever since, that was probably 3 months ago

 

Checked with TA they said it might be transmission gear box failure. Heading to dealership.