I have an '02 D with the 4.7, roughly 126,000 miles. Head gasket was replaced about a year ago. I suffered through the 95+ temps and ghastly humidity the past few weeks with no A/C. It blows okay out of the vents; well, as good as it always has...never was great, and the vents next to the windows blow about as hard as a 95-year old smoker with emphysema! The air seems a "bit" cooler coming from the rear A/C vents, but the air coming from the front vents is warm, and blows hotter as the outside temps increase.

We haven't taken it to the shop for any diagnosis, as we're kind of strapped for cash these days. Just want to know where to start and if there is anything we can check and/or fix on our end before taking it to the stealership.