2012 cascadia owners

When you get a chance...stop and shut engine off. Leave in gear so it wont roll..leave brakes released..watch air guage(s) see how quick air psi decreases. That should tell you if you got a leak somewhere. If you have a leak chock wheels and search it out. May have to fire it up and build air again as some leaks are not as audible when psi is lower. You are aware that air ride does consume air psi as you drive? Depends on the road etc.

 

that seems like it's a fast enough leak to find it fairly easy ... that year the Cascadia leaks just about everything at one time or another ... at least air is free .... if you can't find it easy listen under the flap by the Def tank .. try first with truck running and just feel around that area .... when truck is off def pump is off .. but a fitting still leaks ... it's hard to get in there to fix but doesnt cost much

 

I had a 2013 Western Star with the same DEF system.
Yes my compressor cycled about every 6-7 mins due to the air operated DEF pump.
If you are down to four minutes, then something else is leaking.
My newer 2016 Cascadia has the electric DEF pump, the compressor only cycles about 20 plus minutes or so.

 

my 2012 cycles every 13-15 minutes and its dropping to 105 then goes to 125-130

 

Definitely a leak my trucks have 2 Freightliner Cascadia 2012 they don’t run ever 4 minutes. That’s crazy.

 

Never timed mine. Rare to see the gauges go under 100. Under 110 for that matter.

The only times I have noticed it cycling fast is when there is a problem with the trailer.