On Thu, 20 Jul 2017 17:37:16 -0400,
wrote:

I don't own a pickup so I just skimmed this part, but, as an example, CR,
released today an article that shows that leaving the tailgate open on a
pickup truck, apparently, worsens gas mileage.
http://www.consumerreports.org/cro/c...nomy/index.htm
There again it depends on the truck, and speed, and a whole lot of
things (like what's in the box)

I'm not going to argue because all I know is what CR said, which is...
http://www.consumerreports.org/cro/2...-gas/index.htm

"Tailgates and tonneau covers
We tested a 2013 Ram V8 on the highway at 65 mph with the tailgate up,
tailgate down, and with a factory soft tonneau cover. The tests were
performed following our usual procedure for testing highway fuel economy,
including making runs in both directions. We found that adding a tonneau
cover or lowering the tailgate hurt fuel economy, rather than helped it.

With the tailgate up and no tonneau, we got 22.3 mpg. Dropping the tailgate
decreased efficiency to 21.5 mpg. That 4-percent difference means that
driving the Ram all year exclusively on the highway could cost the owner an
extra 20 gallons of gasoline. (In reality, this big workhorse is likely to
see a mix of driving and a variety of chores, limiting the potential
penalty.) We found that covering the bed with a soft tonneau cover was even
more detrimental, dropping fuel economy to 21.4 mpg."

RAM test:
http://www.consumerreports.org/cro/n...arks/index.htm