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Q: cooling system on 2006 Ford F-350 Super Duty

I am having a problem with the heating. The heat in the truck gets cold, I have checked the water and put about 2 galons of antifreeze in and still having problem. How do I check the water to make sure there is enough. I slso have a whistling coming from under the dash and Its driving me crazy.
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The coolant will be low in the radiator if there is not enough. The coolant reservoir level will probably also be low. If there is still air in the cooling system, this will affect the heat output from your heater. Why was the cooling system so low on coolant, do you have a leak? A problem with the temperature blend door can also cause no heat output from the heater.

Is your truck still under warranty? Is the whistling coming from the engine compartment possibly?
How did you add the 2 gallons? The radiator has a removable cap on top usually. Do not remove the cap unless the engine is stone cold. The cap holds the coolant under pressure so removing the cap can be hazardous when the coolant is hot. You might consider taking the truck in to be diagnosed
I looked closer at some photos of the 6L diesel and it looks like the coolant reservoir is pressurized, like many European cars have. If you added coolant to the reservoir, that is the same as adding it to the radiator. Sorry for the confusion.

Still I am concerned that you were able to add so much coolant. Has the truck been smoking from the exhaust at all?
Yeah a little black smoke is normal. I've heard a lot about the (liquid cooled) EGR cooler leaking coolant into egr passages so the engine ends up burning coolant. It can look like a head gasket with the white smoke.

There might still be air in your cooling system but I haven't been able to locate a drain and refill procedure for the coolant. Many cars have a bleeder screw that needs to be opened when you fill the cooling system but I can't find anything about that in my manual. When the truck is at operating temperature, feel the heater hoses to make sure both are warm/hot. If one is cold or significantly less warm, you're not getting the coolant flow through the heater core.
I have no leaks that I know of there is no water in the oil. How do I get water in the radiator if it is low?
There is no radiateor cap on the top of the radistor, thats why I cannot figure out if the fluid is full. I will make an appointment for next week.
my 2008 350 Ford Diesel truck's air conditioning works at a minimum even on high speed. Seems to be alot of dirt coming out of it. I've had the A/C checked, but no one has been able to fix it. Any suggestions????
whistling coming from under the dash. Heater Blower Motor »
No heat in the truck, Heater Core or the Heater Control Valve »
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