I've got a 2001 F450 bucket truck with V10. XL trim but it has air conditioning.
Last year I recharged the system and it worked for the summer season. This year it's not working again. 5 or 6 days ago I put a 12 oz. can of refrigerant/sealer in. It did nothing. Today I put another 12 oz. can in. It got cooler but it still isn't where it should be. I can see no obvious leaks like I could when I had to replace an accumulator in a 2007 Crown Vic.
Is it possible that I still need to add more even after already using 24 oz.?

 

One of my company trucks (a '94 Silverado) had to be charged every summer, sometimes twice during the AC season. After a deer committed suicide on the front of the truck (I was going 65 MPH) the repair shop found a cross-threaded connection on the line from the condenser coil. It came that way from the factory. It never leaked badly enough to leave an oil trace.


Call around, some HVAC contractors as well as larger automotive service centers have a "sniffer" leak detector that can be used to pinpoint the leak. It should take no more than an hour, and you don't get dragged into guessing and changing parts that aren't bad or endlessly dumping Freon into it. Be sure they check around the pressure switch on the accumulator as well as the line connections.

 

After the third 12 oz. can of refrigerant/sealer it's cooling off properly now. We'll wait and see how long it holds up. Kinda sucks to throw about $60+ at this every summer.