I Have A 96 7.3 Psd And It Sits All Winter Long Because I Have A Seasonal Asphalt Business And Was Wondering If I Should Start This Every So Often And Let It Sit And Run And When Should I Do This And How Often.

 

For the winter I wouldn't worry about it. It might be just as bad for it to sit as idle for a while but never get to temp. It creates condensation in the engine which turns to acid in the oil. I would go out and run it for an hour down the road on your way home fill up the fuel tanks full then park it.

edit- also make sure your coolant is good enough to protect against freezing and it would be good to remove the batteries and keep them warm in your basement or something.

 

If your going to let it sit I would add biocide so it doesn't grow algea.Maybe change oil so it doesn't have old contanimated oil in it.

 

Where is biocide available?

 

i would just give it a good drive once a week, remember there are transmissions and rears too, not just an engine to worry about