0 air pressure to truck, help would be greatly appreciated and DPF issue

Hillard, if your compressor is working. The air has to go somewhere and you would hear it.

You know what a blowing attachment sounds on the end of an air hose.
If you had a line come off you will hear that noise, may not be as loud but similar.
What/how did your truck operate before you had zero pressure.
Did it slowly lose air while driving. Were you parked and it wouldn't build.
Did you lose it while applying brakes.

If you can't hear any air leaking even while motor is running. The first thing I would do is disconnect the supply line from your compressor and make sure your compressor is working.

 

My DPF replacement for $2,800 did not have any issues other than it was just time to be changed. They are only good for something close to 9000 hours before they plug. At just over 8,000 hours my ash accumulator was reading 98% full, so I had the DPF's changed out pre-emptively.

 

My only guess is someone took it out. That valve wont just come out. Well, I haven't ever seen one fall out.

 

If someone removed the valve, or replaced the valve without adding new thread sealant, it will back out. So clean threads with a solvent, apply new sealant, reinstall and forget about it. Thread sealant will act as a thread lock, but as with thread lock, it requires clean surfaces.

 

You can blow DOC with air, but you in order to clean DPF you need to bake it

 

We've done it with a hot water pressure washer before. It works, but not nearly as good as baking.