Yes get the head checked by a competent machine shop. Cracks and warpage are not always seen with the naked eye.

In my experience a blown head gasket or cracked head will make milky oil....not milky coolant. If your truck is an automatic it could be just that the transmission cooler inside the radiator is leaking. Or it might just be sum nasty old coolant. Does the coolant look like is has lots of shiny particles in it? If so its stop leak, which can clog leaks and unfortunately clog the radiator/heater core /etc.