Approx. % increase of mpg while adding bed cover
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I would be more interested in how a topper affects MPG. I know the bed cover on the 09+ has no effect, on the 01 it helped a little, just enough to notice at the pump, but not enough to offset the price of one.
On the 12 I had, it got the same MPG with it as without it, mainly because it played the same effect as the air bubble did. The one thing however that it does do is play the air bubble at all speeds, so it does increase aerodynamics at certain speeds, but not enough to affect overall MPG. It was mentioned earlier about the tail gate wing, that is what makes the difference between the 09+ and earlier models, the rounded tailgate on the 01 did not help reduce drag, but increased it so the cover did help somewhat.
On the 12 I had, it got the same MPG with it as without it, mainly because it played the same effect as the air bubble did. The one thing however that it does do is play the air bubble at all speeds, so it does increase aerodynamics at certain speeds, but not enough to affect overall MPG. It was mentioned earlier about the tail gate wing, that is what makes the difference between the 09+ and earlier models, the rounded tailgate on the 01 did not help reduce drag, but increased it so the cover did help somewhat.
Approx. % increase of mpg while adding bed cover
...10% improvement in aerodynamic performance is good for a 2-3% improvement in gas
mileage, based on an EPA road speed of 48 mph. Therefore, an improvement in Cd of 5.73%
could account for a 1.8% improvement in gas mileage....
LOL
[/QUOTE]
So that means you gained an astonishing .4mpg at 22mpg! I mean really thats less of a difference than driving into a headwind at 65mph where your garenteed to loose 1-2mpgs. This is a funny thread.
mileage, based on an EPA road speed of 48 mph. Therefore, an improvement in Cd of 5.73%
could account for a 1.8% improvement in gas mileage....
LOL
[/QUOTE]
So that means you gained an astonishing .4mpg at 22mpg! I mean really thats less of a difference than driving into a headwind at 65mph where your garenteed to loose 1-2mpgs. This is a funny thread.
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Joined: Jul 2011
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From: midwest
Couple of things stand out. For one, this study was done by SEMA, which as we all know supports accessory makers. Not exactly impartial. Why go through all of the hassle of testing in a wind tunnel and not following up with a simple road test to see how a cover REALLY impacts MPG? Instead they state "In order to determine how coefficient of drag translates into fuel efficiency (MPG), a simple equation is derived".
A even simpler test would be to test it in real life. I suspect that they did and real world usage didn't support their theory, so they just ignored it.
A even simpler test would be to test it in real life. I suspect that they did and real world usage didn't support their theory, so they just ignored it.
Last edited by zx12-iowa; May 13, 2015 at 06:48 AM. Reason: Stupid auto correct
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From: midwest
Agreed but that's not the question. Takes many miles to have fuel savings pay for cover, but there are small savings to be had
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If you want to get all technical, why did they switch to an aluminum body? To save weight right? Well, when I put my fibermax cover on it also added weight to the truck. Is the reduced drag enough to offset the additional weight? That is another question as well to throw into the analysis.
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From: Calgary, AB
