I have an 03 f250 6.0 150k milage and lately my A/C has not been working at its best. Its intermittent, and for some reason it will work fine until i get on the highway and it just blows hot air. Would this be a leak or clutch issue? One thing I have noticed if my oil/coolant is above 200 the A/C will blow hot air but not return to cold when the temperatures return to normal. I haven't done any trouble shooting so my first thing ill check are the fuses. As far as the compressor goes its an alien object to me I have never had A/C issues with any vehicle i have owned.

Much appreciated.

Caleb

 

Update:
Went out to check the fuses, which are good. Truck temperatures were normal and the A/C was blowing real nice....

I'm lost.

 

Check the clutch gap.

 

Check the tension on your belt, make sure it's snug, check your tensioner also, at higher speeds the belt may actually be slipping around the AC pulley.

 

belt is good, What should the gap be? Is there a tool to measure?

 

Feeler gauges. Anything over around .040" is too much.

 

Not to hijack this thread but i am having a similar issue with my 03. My problem is the ac works great until the clutch kicks off. Then the clutch will not engage again until the truck is cooled off. I have replaced the ac clutch relay and that seemed to help for a short period of time but now it is back to doing the same thing. This problem also only seems to be present when ambient air temp is around 85 or higher. I have checked the freon when it was working and the level is 45 according to the gauge on those cans used to fill the system.

I will note that the relays under the hood are really hot to touch when the problem is happening. Not sure if there is any insulation I can put around the fuse box under the hood to keep it cooler.