Tonneau cover MPG

[nlambert182]

I was seeing 18.5 mixed driving before the tonneau, and still see about the same with it. Never really noticed any difference. I wonder if some folks subconsciously begin adjusting their driving habits with the idea that they're expecting better fuel economy.

 

[zrock]

I seen better fuel econ when i had my truck cap on, when i switched over to a tonneau cover i noticed a slight decrease but never enough to worry about.

 

[sblack33741]

Hey yall
I put a retractable tonneau cover from Truck2go on my 6.4 2500. I watched the TFL guys vid on their MPG test of cover on/off. They showed an increase of 2+ MPG. Well, I got same results!
While I didn’t take a dash pic of before I put it on, I reset my AVG and it was 14.5 mpg on my round trip commute of about 60 miles (28.5 in am, 28.5 in pm)… after I installed it, I reset again after the install and it was 17.3 mpg on same round trip! I wasn’t able to use cruise control due to Houston traffic, but I did try to drive in similar manor on both days. Not a bad improvement and it looks great!

It looks slick.

 

[ECONORAM]

I looked at some wind tunnel data years back, as well as this Popular Science article. https://www.popsci.com/cars/article/2002-07/truck-drinks-less-car/
I've run both a tonneau cover and a topper. Both have helped mpg on my 07 1500 QC. The bed is 6'3"; i don't know if that's short or long. My best is 21-22 mpg at 70mph on the interstate. 24-25 mpg at 60mph if I will go that slow. However, the tonneau was a bit better than the topper if there were several stop and gos, 'cuz it weighs 200# more.
I could probably look up some trips from my pickup's early days, but one that sticks in my mind was getting 16.5mpg @ 65mph with less than 4k on the odometer.
Now at 176k it will see the figures above. True, I did add more than just a bed topper...

One proviso: all these figures are on 100% gas. Although I think I can match the 24-25mpg at 60mph by using E10 and Superchips Towing Tune. I'll maybe try that sometime.