I heard of a similar problem in Oct '12 when I was on my way back to MN from California with my used fSBO '99 Lazy Daze. I met an owner of a brand new (at that time) Lazy Daze (Ford V10) and he said it was burning oil. Hopefully your issue is resolved now.
My '99 (104,000) burns no oil just running around here in MINN. It did burn up a little on the way back from CA in '12.
I check it regularly and have it changed in the spring and fall regardless of mileage. It's cheap insurance and I like to have the Ford tech do an inspection each time.
I want to be out front of any maintenance issues especially on an older unit like mine.