2004 f350 5.4l doesnt heat when temperatures drop below 40 degrees. Truck has no cabin filter. Co worker said it could be a water pump and thermostat. What do you guys think on what it is? Sent from my SM-G975U using Tapatalk
Thermostat is very likely, but when was the last time the coolant was flushed? Coolant starts to drop out solids when it is old, or mixed improperly. The congealed solids collect in the heater core, radiator, etc. Coolant is often the most overlooked maintenance item in every truck. If it were me, and I had a 17 year old truck north of 100K, it would get a really good flush, with a 2 part chemical, a water pump, and a thermostat. If it was my daily driver, the hoses would get replaced, too.
Very good info. The other item that gets overlooked is the power steering fluid and differential fluid.
