For those of you who have DEF systems on their trucks I found out something worth knowing today 
If you don’t drain your air tanks every day moisture gets into the DEF system and can cause the fluid to crystalize and form a crust in the pipes, eventually blocking it and causing engine shut down. Not that it has happened to me, but a Frieghtliner mechanic told me.
just thought you’d like to know that 
Am i being a silly billy to ask what a DEF is■■? 
Deisel exhaust fluid, for use in a Deisel particulate filter. From what I gather, in the UK drivers buy it in little cans, over here it’s sold at the pump.
Pat Hasler:
Deisel exhaust fluid, for use in a Deisel particulate filter. From what I gather, in the UK drivers buy it in little cans, over here it’s sold at the pump.
Oh right. We call it AdBlue. I don’t understand how the air system can be affected by that. From my limited knowledge, they are not connected to each other. No doubt ill be proved wrong though. 