I haven't been here for a while but I was redirected today. Someone mentioned Anchor Motor Freight and a 53 COE. I have photos of many old Anchor Clankers. Here's a photo I shot on a Sunday in 1985. Anchor's big yard in Baltimore. These trucks were not idling but in years before that, when fuel was cheap, Anchor left their truck running at idle all night.
Baltimore, 1985 by
Dick Copello, on Flickr