I took another 50 mile trip today up the hwy. This time I drove like I normally do, no coasting tricks. I kept it to 65mph. But before I did I had a piece of plywood, about a 4x6 sheet. So I bolted it down and used it for a sloped cover right behind the cab. But it ends 3/4 of the way before the end of the bed. My question is, does this do any good? Or is it just moving the area of drag over the top of the truck from directly behind the cab to 3/4 down the bed? The scangauge read 24.5mpg average today. So that's consistent where it always read about 20.
