Tonneau cover vs camper shell


#1

I READ THAT A TONNEAU COVER WILL INCREASE YOUR GAS MILLAGE ON A PICKUP 11%, WILL A CAMPER SHELL DO THE SAME?


#2

I think that’s a load of bunk. The drag caused by a pickup bed with the tailgate closed is negligible.

I used to have an S-10 that came with a bed cap. The thing was really heavy, at least a few hundred pounds. The truck felt a bit sluggish with it on, but ran much easier with it off and got better mileage without it (not a lot, mind you).

This sounds like the sort of thing a tonneau cover/bed cap manufacturer would say. Any difference would be miniscule, and fuel savings would be immeasurably small, if present at all.


#3

The cover won’t increase the gas mileage but the camper shell will lose about three miles per gallon. Most camper shells are wedge shaped and will kill the gas mileage.


#4

I had a cap on my 95 Dodge Dakota Club Cab pickup for about 3 or 4 years of the 8 years I owned it. There was no noticeable difference in gas mileage with or without the cap. I suspect a tonneau cover wouldn’t have made much difference either.

Ed B.


#5

11% may be a bit high and it certainly is not universal. Different trucks have different shapes and the results of this or that on mileage will vary greatly.

Run 10 test with different trucks and speeds and you will get 10 very different answers.


#6

Some years back Consumer Reports tested the tonneau-cover-saves-gas claim. It’s pure balogna. It has zero effect.

A shell will have an adverse effect by creating a larger low pressure spot behind the truck than the truck would normally have. Larger shells that extend above the cab have an even more adverse impact by increasing the “frontal profile”, that total amount of area that the truck has to somehow open the air around it to get through.


#7

I had a S-10 for many years and about half of the time I had a cab high shell on the bed. I did not determine a difference in fuel mileage between the shell installed or off and I was habitually checking each tank’s mileage. However the truck was quieter due to the wind not hitting the rear cab window and the suspension was more effective and smoother with a small load on the rear springs. For my purposes the shell was a good fit. Plus I sold it for almost what I paid for it


#8

thanks for your input. I just saved several hundred dollars


#9

Thanks for your input.


#10

Thanks for your input.


#11

Thanks for your input.


#12

Thanks for your input.


#13

Thanks for your input.


#14

Thanks for your input.


#15

Thanks for your input.


#16

The answers are right. It’s a myth that a tonneau cover or shell will improve MPG, especially 11%. Mythbusters did a very careful experiment on this a while ago and it was found the best MPG was had with the tailgate up (not down) and nothing on the bed. In other words, a plain looking pick-up. The rolling vortex of air in the bed acts like a spoiler guiding the air. I’d guess that a shell would be the worst because of the extra weight.


#17

Cool. I myself installed a sliding rear window and I loved the wind blowing in the back window.

I also worked 103 miles from home for a year, commuted (yup, I’m nuts) on mostly highway, and experimented with having my tailgate up and down. Absolutely totally no difference in mileage on my truck.