Good to know. Thanks for the info.

One more question - how do I keep this from happening again in the future? The first week I got the truck, the check engine light came on with the same overboost code. It was covered by warranty, and they just pulled the turbo and cleaned it. That was two and a half years ago.

This time, the wrench light came one (not sure why it wasn't the check engine light). Should I expect to have to pull the turbo and clean it every couple of years?

FYI, my truck sits for one or two weeks at a time, but gets driven on the highway when I do use it (usually at least 100 miles at a time). Half of that time, it has a trailer on the back (anywhere between 3500 and 9500lbs), so it does get a work out. When the truck is empty, I try and goose it every once in a while to keep the turbo 'worked out,' but apparently I need to do something else. My daily commute is only a mile, which is why I don't drive the Ford every day... I figure that it's better for it to sit for a week or two instead of being driven such short distances all the time.