Didn't expect this on Fathers Day... driving a 1999 Blue Bird Mini Bird bus diesel with 90K miles, from Canton, GA to Nashville, TN and I couldn't get up to highway speed. So I decided to take the state routes and back roads, and just past Lookoit Mountain, I couldn't make it up the next hill. Once I sludges to the top at a cool 2mph, I pulled over and called for a tow. Anyone have any ideas what it could be and potential cost? One mechanic on the phone said it could be a turbo issue? Thoughts?