Tonneau cover and mileage

[nicholg2286]

I have heard that putting a tonneau cover on your bed will increase your fuel mileage. Does anyone have any data to support this? It sounds reasonable to me - given the aerodynamics, but before I go spend $750 on a cover, I would like some real data - not just the word of the salesman.

[Kennedy]

I wouldn't spend the money on a tonneau to save fuel as you'll never recover it. Put a cover on to keep stuff inside etc. You can buy a lot of fuel for $750.

[Craig M]

There was some test data done at a university posted on this site a bit ago. They ran a model truck in a wind tunnel in various configurations. With cover, without, etcetera. Data was interesting. Their units were metric, and the conversions did not make sence (140 mph). I e-mailed them to try and get correct or original data and the reserch team did not reply.

[AndyL]

There was some test data done at a university posted on this site a bit ago. They ran a model truck in a wind tunnel in various configurations. With cover, without, etcetera. Data was interesting. Their units were metric, and the conversions did not make sence (140 mph). I e-mailed them to try and get correct or original data and the reserch team did not reply.

Metric results? link?

[Arlie]

Mythbusters did testing on tailgates, with, without, and with the mesh style.
Methodology wasn't great but enough to be able to say there weren't major effects (slight advantage for the mesh). I'd bet it's similar for a bed cover. The main wind resistance is from frontal area.
Kennedy is right, you'd never get your investment back.
Arlie

[JohnC]

I've always had one, primarily to cover the box. I've always felt it was good for one MPG or so, but I understand there is data that contradicts this. I've never paid more than $350. Currently I have a Torza Top (sp?) that's a snap to remove if I need the room.

[mark45678]

Save your money on fuel... set your tire presure to to max like the door jamb say , that will do more for mileage then any other mod. Keep it blow 2000 rpm and drive like you have a raw egg under your foot...... If your really worried about fuel economy Buy a VW TDI, 3 time better on fuel and 20,000 cheaper new. but your going to get a few looks when you show up at the camp grounds with a 35' 5th wheel hanging out of the back window.....

[Craig M]

Have heard from more than one source that removing the tailgate from an uncovered truck actually hurts mileage. This is contrary to what many people think. Vortexes and wind swirling can do all sorts of things.

[carco]

I've heard what CraigM said. I run with tailgate, run light throttle except when I need a "seat of the pants" kick. mileage ok for 7000#+ vehicle that performs better than a lot of cars. bob...........