A/C recharge port

[05norcal150]

I'm trying to add some freon to my AC as it doesn't blow very cold...where exactly is the low pressure line located and what does it look like on my 05 5.4?

[Raptor05121]

Why do you think you need refrigerant? (freon was banned years ago). Is there a leak? Is your compressor cycling on/off? Adding refrigerant isnt going to make your A/C colder, nor could it even be low. The first thing you need to do it take it to a shop and let them check the refrigerant level, many places do it for free. Or you can go to Wal-Mart and get a can of r-134a with one of those plastic gauges, but I wouldn't trust those and you might not even need the can. But whatever you do: DO NOT OVERFILL IT. An underfilled system is better than overfilled when it comes to air conditioning.

Your low-side port should be on the accumulator, which looks like a giant aluminum soda can, on the passenger side firewall. It should have a black screw cap over it. You can locate your air conditioning compressor and follow the lines back. If the R-134a level is good, stick a thermometer into the middle vent and test various settings (fan speed, compressor setting, trucks speed, etc) and come on back with those temps and we might be able to help you some more. The 2004+ trucks are notorious for sucky A/C, so you may have to deal with it. My 1998 F-150 blows 38* cold in the middle of the summer at full cool, but my 2006 F-550 can barely keep it below 45*F.