My 2007 GT has developed a slow freon leak somewhere. It started running low on freon last May or so, and it seems to be depleted again (about 8 months). Is there a likely culprit here, or anywhere I should investigate first? Maybe something has just come a bit loose? Thanks!

 

Mine leaked out through the compressor seal on my 05. Dealer covered it as there was a TSB on the seal and the car was still under warranty at the time. Might be a good starting point.

 

x2 on compressor seal here. $24 part and Ford USED to just replace it.

But of course they figured they could rape us easier if they stopped replacing the seal and require complete compressor replacement AND make it in many pieces as a kit (clutch, pulley, and compressor are different pieces you buy and they assemble them at the dealership). I verified this with at least 5 dealerships within 300 miles of my town.
total cost for them to replace a (what should be) $24 compressor seal in my '07? $1300.

If you are mechanically inclined, I'd suggest doing the seal yourself and taking it to the stealership for a recharge afterwards. You'd save at least well over a grand this way.