Vehicle is a 2000 XLT Reg. Cab F-150 V-6.
Problem:
A/C is not cold as it used to be, or as strong. It still works and works well since I closed off the farthest vent. But now it takes quite awhile for it to blow cold air and the air that is coming out is both weaker and not as chilly as it used to be.

Even in the disgusting humidity I used to be able to freeze my co-passengers out without even hitting high on the panel.

What could cause the pressure drop and temperture raise?

Also how much should a drain and refill run? Pep boys said 150 with no diagnostic at all so I won't know if anythings wrong until after I've already been stuck paying for a perhaps unneccesary refill.

If anyone knows of national chains that do a diagnostic cheaper that would also help. Or if there is a way for me to check it myself without any prior knowledge of it. Someone in another post mentioned feeling two pipes while the a/c is cycling. Which two pipes?

Sorry for the longwinded questions, just want my freezing cold a/c again as it's been slowly doing this for about a year and is finally driving me nuts.

 

It just sounds exactly like mine did, all I did was take it to a rad/ A/C shop, standard inspection fee and all that was wrong was it was just under 1 lb of refrigerant. No drain, just a top up and it snows in there now. All that for under 90 bucks. Run the truck to operating temp, open the doors and turn A/C on full everything. Under the hood at the firewall (passenger side) you should see a can with 2 pipes going into it that also go through the firewall. They are aluminum in color, 1 bigger and 1 smaller. They both should be close, like 10 degrees of each other. Also, see how often your compressor cycles, because it shouldn't be frequent, if at all.

 

The 2 lines are in line with the passenger side (or right side) cam cover. There is a bit of rubber hose accounting for half of the tube, but feel the metal part. Guaranteed you're just low on refrigerant.

 

Well I finally got a chance to use your suggestion and one line (I believe the one closer to the firewall) was probably 15 degrees colder so I'm going to take it to an A/C shop since as you said it's probably just low on coolant.

I listened for the compressor cycling and it was about every couple of minutes, maybe longer. I am hoping that was due to the extreme humidity and upper 90's temps. outside.

Thanks for the help now I'm less likely to get gouged since I don't know much about auto HVAC.