I'm reposting this message from last year (not my research). I copied it to a text file without the headers, so my apologies to whomever originally posted this. I did this fix, and it works great. Cost me ~$11.
I went to my Friendly Dodge Dealer today and purchased the oil cap #53032389AC, and the baffle that goes inside the oil fill neck, #53032126AA. All this cost me 9.00 TTL and will eliminate the moisture build up in the 2K 4.7 motors. Just wanted to share the info in case some of you out there have this moisture under cap problems..You need the new Cap along with the baffle to make this work correctly,the new Cap is designed differently than the old style cap.