I took the leap. I flushed out my trans today and put in Mercon V. I did the Prowler 7-6-3 method and replaced what was in there (who knows) with Mercon V. It has 99,867 miles on it with factory external trans cooler for towing package. Initially, no change whatsoever. Shifts the same. We'll see as time goes on. I was going to do a visual write up but I'm glad I didn't now. Had a bit of a mishap. I had the wife starting and stopping the engine for me while I monitored the milk jug filling up. Only problem was, she started the truck before I was under there. Only a little spillage. All in all, it went well. I'll try to keep an update as the mileage racks up for those of you that have been contemplating doing this.