I had this issue as well, and I was just talking about this in a different thread with someone the other day. Mine seems to have gone away when I replaced the radiator cap for a brand new one. Your system uses pressure to raise the boiling point. If the cap lets off steam before a certain PSI you are boiling off coolant. I would maybe try this. I think the cap cost me 12 bucks or something like that. Easy fix.

__________________
97 Ranger - 4.0 V6 auto, 4wd, 31x10.5x15s Wild Country XTX Sport All Terrains, Warn locking hubs, Pioneer deck with iPod attachment, Snugtop Topper, K&N filter, scan gauge II, Hella 500 Lights, More parts coming, waiting for the paycheck to get bigger!

Truck built in loving memory of Norm Howard
Outcast Racing
PNW Crew!!!
Afterhours Clan!!