I don't know but I'm hoping someone will provide an answer. I have a 2001 Honda CRV with roof racks and I'm guessing that I'd see about a 1-2 mpg increase if I removed them for long trips. I do use them occasionally (about twice a year) and I'm thinking that it's likely that I'm paying a dear price for leaving them on all the time.


If I only remove the cross bars, it would be easy to do and I think most of the drag is from them.