Our new truck doesn't have a tonneau cover for the bed, and we're thinking that it would probably improve aerodynamic performance (and mileage) if it did. Does anyone have experience with adding one ...
I have a Hard one that came with my truck, I have not had it on for the last year and a half and think my mileage is about the same, give er take .5 MPG. I liked it for the storage and theft protection. But I can not use it, since we got the new dog and I need to take him in the crate.