2012 Ford E-Series Van • 25,000 miles

We own a fleet of Ford E series vans years vary 2000 to 2013 all of them have moisture that builds up between oil changes under the oil caps. I was told that this 1 or 2 things that we do that causes this. 1) We have never had the PCV changed on any truck since they were bought new. 2) We have a idling policy that requires our driver to shut the truck off and restart at every delivery. Each delivery takes about 1 to 2 minutes each. And more time than not the locations are 2 to 10 miles from each other. Each route has between 40 to 60 stops each night. Is what Im being told true and can you explain to me why this happens?
Wayne Anthony Pearson
January 21, 2013.

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