Bed shell effect on gas mileage

I think it cancels. My ARE Z had no effect on mpg.

I'm gonna ditto BAC and what you've said as well. Any improvement in aerodynamics would be offset by the weight. It's a wash.

Unfortunately, I can't say how/if it had an effect on my gas mileage. I had the shell installed right around the same time I switched to synthetic oil.

That said, I got 17.8 MPG on a trip from Prescott, AZ back home to Temecula, CA. That was with the shell, 3 dogs, 2 adults, 2 kids, 2 wire dog kennels, luggage, some food, kid toys...pretty full. Averaged 70-75mph on the freeway, had some traffic, some country roads. Made the trip without stopping once for gas. Roughly 360 miles on just over 20 gallons, which I consider to be really good.

It really comes down to what type of driving you are doing. If you are doing mostly city driving, then the shell is not really worth it to save gas - might even drop some. Yes aerodynamics are better, BUT its more weight. NOW, if you are doing alot more highway milage, the weight isn't really a factor, and you do see an increase in MPG. Hope that helps.

Astudty was done a while between two trucks; one with a bed cover and one without. They had these two identical trucks on an oval track and the one with the cover average between 2-5 mpg and the other with the tailgate up and down didn't fare so well on milage. Some thought that driving with gate down help improved the gas milage, however it didn't. Like the above mentioned city driving wouldn't yield a difference.

i had a tufftaunno on my f-150 and didnt really seem to help much if any they said it would but not enough to make a difference i crap 3 pennies a mile