New truck same problems

Can you just leave the key in the off position to avoid hearing the low air alarm?

Are you popping just the tractor brakes or both?

You have a leak somewhere, clearly on the tractor. Check your bags and cab bags but I'm leaning towards your bags by your drive tires.

 

Check the range selector switch. Mine was leaking only with the switch in the up position (which it needs to be for opti-idle to work). Took me a few days to diagnose because frankly I didn't think to check it but asking around (other FL drivers and our mechanics) it turns out it's a VERY common problem with the Cascadia.

 

It's probably the air tanks themselves many of the new trucks have automatic dump valves that bleed air from the tanks while it's parked. I've seen it on new pro stars Cascadia's and Peterbilts.

 

And yes it's VERY ANNOYING having to listen to that racket everytime you get in a truck you just pulled into the shop 4-5 hours ago.

 

When it drops are both tanks low, or the primary or secondary only? Most of your cab stuff and suspension has a safety valve that should not allow air to drop below 90 psi. So you can rule out suspension, cab suspension, seat, etc., unless that valve is bad, which is unlikely on such a new truck. If your losing air out of both tanks, you have multi problems. You may have to find a quite place to park, use some soapy water in a spray bottle and go hunting. It is not uncommon to find several air fittings leaking on a new truck. Mostly I find push in fittings not pushing in all the way. I also see poor routing and/or zip ties too tight pulling on fittings making them leak. Quality control has taken a back seat to cheap labor these days when it comes to final assembly.

 

the OP said it was a AUTO-SHIFT

 

I call them snap-together trucks. They use those quick fittings to slap them together. Then you get a minuscule leak on 10 of them and that equals 1-2 major leaks. You can't find them all. THE ONLY trucks I ever see that hold air pressure better than 90% of the trucks out there are old farm trucks. I guess the mud and crud seals those small leaks. I can have a 2010 and a 1988 sitting in the yard and the 2010 might lose it's air in an hour and the 1988 holds for weeks.