Alright... Here's the story 2008 6.4. Heat stopped working 2 weeks ago. Was about 3 gallons low. Added coolant and heat started working. Today it stopped again and had to add 1/2 gallon of coolant. No coolant leaks on any hoses, radiator is less than a year old. Checked oil dipstick and could smell coolant with the oil.... What do I have to do now???