Those International diesel engines in the Ford trucks use the engine oil as hydraulic oil to actuate the fuel injection.
Don't worry about foaming. Ford requires an oil with the API rating CI-4, and all CI-4 oils contain a suitable amount of antifoam agent.
For your Maine winter and quick starts, I'd use either a synthetic oil like Mobil Delvac 1, Shell Rotella Synthetic, Petro-Canada Duron, or Schaeffer's #700 (premium synthetic blend). All are CI-4, none will foam in the engine, all will best protect the engine in cases of cold starts and quick get-aways. All will be very good in your whole diesel fleet, not just the Fords.
Because of the unique fire duty...cold starts, lots of idling, few miles, I'd do a program of oil analysis to get the most for your money from these expensive oils.
Ken