I replaced the thermostats 3 weeks ado when this issue started. The problem is still there . The fan clutch will engaged and the temp sensor pegs at hot.When I reduce speed the temp goes back to normal and the fan clutch will disengage. Sometimes the green wrench light will come on and the dash will read reduce engine power but not always. There is also no heat blowing from the heater. The heaters core hose are both cold even after driving for 20 minutes. the top radiator hose is hot but the bottom house is not. The coolant level stays around or above the cold fill line . There is no coolant in the oiL. Would this be a sign of a failing water pump or head gaskets? Thanks, Kevin

 

Almost sounds like an air pocket, cavitation.

How many miles?

Which year?

Are the plastic connectors on the main radiator hose white or black?

 

2008 F350 4x4 Dually 170K miles

 

I did replace the ect sensor about 3 months ago but did not have this issue until 4 weeks ago

 

the connectors for the hoses are black

 

I found reference to a TSB where Ford replaced the hoses of black connectors which have one seal, with hoses of white connectors that have two seals. Because of air seeping into the coolant system due to suction, resulting in cavitation and no water flow.

I would suggest that you talk to your local Ford Parts Counter as they can show the part supersession.

You have probable caught it just in time.

One way or another, time for new hoses at a minimum.

 

This is a good explanation

 

Ron holds the hose with white connector in the first few seconds of the video.

 

thank you I will check with them.

 

My hoses were all black ends as well. My dealer tech told me that they would only replace them if after a pressure test they were found to be leaking. Just to give you a heads up, and I would have to pay for the pressure test.

 

Amazing how, if you ask a service tech how to solve a problem they will suggest service and replace parts IF they can find a problem.

 

Is this a stock truck?


so how old is your degas bottle pressure cap???? Invest 5 bucks and get a new one. Old caps don’t hold pressure well. Coolant needs to be 16 PSI for max boil over protection. Coolant that is boiling creates air bubbles and that does not transfer heat very well.

get a hydrometer and check the coolant to water ratio. Too much water and the coolant heats up faster ....


coolant / oil exchange cooler could be clogged

dpf could be clogged

cat could be clogged

ait filter could be clogged

check your fuel cooler for correct coolant and if you never replaced the 20 psi mini cap...invest 7 bucks for that

check oil for coolant

check coolant for oil

any funny smells

opefully you do not have a tuner with a 500% tube and dpf still installed...