My 2008 F250 w/ auto air conditing will only blow hot air after the truck is out in the sun for a short time when it is cool in the morning it works fine..

usually means the interior heater is block and will need back flushing to remove the build up in the heater water lines and elements.

Yes I am find to drive

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could be slightly low on charge-or cooling fan is not working-as the temp outside goes up the ac needs to be more efficent to blow cold air--and really 55 is not that cold--depending on outside conditions should be able to blow at low to mid 40 s

It sounds like the dual climate control valve. It is supposed to close the valves when the a/c is turned on, but they get stuck sometimes. I have already replaced 2.

What happens is the valves get stuck and the engine heat will blow over the cool air making it feel warm, even though the a/c is working fine.

If it started out on one side of the car cooling better than the other than you can almost bet this is the problem.

They will be called a heater control valve by most auto parts stores. I think the part is Motorcraft YG378.

Another way to make sure this is the problem is to find the dccv and clamp the two top black hoses with pliers or something and see if the car gets cooler. It will still not get cold but this will let you know if the dccv is the problem.

I worked at a Dodge dealership for a while and 9 out of 10 times this is due to the recirculation door being broken, allowing hot air from outside to enter the cab of the truck. The dashboard will need to be removed to access the area.

Confirm that A/c compressor is working when cool is lost
Do you have auto climate control?

It sounds like your air conditioning is actually not the issue here. If your a/c is working in the morning, there is no reason it shouldn't work at a different time of day. What most people don't realize is how hard an a/c system must work to cool off a car that has been sitting in the sun all day during a hot summer. Even if you leave your windows down to avoid the greenhouse effect (which can make a HUGE difference if you don't) the interior of your vehicle is still probably a dozen or more degrees hotter than the temperature outside. This is because only so much air can circulate through cracked windows, and because of the direct sunlight shining onto your vehicle's interior and upholstery. Even once the a/c system is up and cooling the air inside your car, it is still struggling against the heat stored in your car's interior, which is giving up its heat to the surrounding air as it cools off. This can take quite awhile, and if your drive home is a short one, the a/c system may never have time to fully compensate once the car's interior has cooled to match the interior's temperature. To make matters worse, if your drive home is one through the city, you can expect your a/c to suffer. The air conditioning system needs good, steady airflow over it's condenser (a radiator-type part located just behind the front grill) and lots of starts and stops in a city or heavy traffic area can obviously prevent this. Above all though, the most important thing to remember is that with even a perfectly functioning a/c system, you can usually only expect about a 30 degree drop on average from the outside air temperature. So, if it is 100 degrees out, depending on the ambient pressure and humidity (also things which can affect an a/c system's efficency) you may only get air that's 70 degrees out of your vents. I would recommend always rolling your windows down half an inch or so, and park in the shade whenever possible. Also, putting a sunshade in your front (and sometimes even rear) windows, and having your side windows tinted (when legal) can go a LONG way toward keeping your interior as cool as possible when sitting parked in the sun for long periods of time

Sounds like your freon has leaked out and your heater blower resistor is burned out. Deffinitly take this to the dealer.

Sounds like there is either

1. Too much freon in there

or

2. Not enough freon in there.

Freon (R) being freon or low CFC equivalent.

Sounds like the system is working fine, then the condensor or compressor gets too cold and freezes up (or gets WAY too hot). when you turn the A/C off, the system has time to stabilize and return to a more 'normal' condition.