[gumby79]

Before the bug shield.
The wipers had a significant aero load on there down stroke.

And they woud be pushed slightly up the windshield.

Rain accumulatios and water puddling from the wipers would be pushed up the windshield in a radiating sun ray like pattern with short straight drop streeks keeping the windshield mostly clear.
Bug strikes went from sheet metel just below the windshield gasket up. Grass hopers and dragonflies wedging under the wipers are the worst

This is the typical pattern I've seen on my truck naked. Including in tuft testing .


Now with the bug shield
The water flow on the hood is reversed flowing to the front corners insted of to the rear.

Water on the windshield will sits virtually stationary getting buffeted wiggling up and down and slightly to the out sides. This requires use of the wipers more frequently,as the water will form into ribbons and dots. Puddles no longer get pushed up and off the glass they now go down into the calw vent.

Bug strikes are now in the parts of the truck seen in the image below, only the top 4-6" of the windshield has bug strikes, above my line of sight . Were every square inch showin has 1-10 splattered bug from my last run from Montana to Ogden,Utah on May6 . There are 10 total strikes on tbe lower part of the windshield




Not having to stop and scrape the bug mill off the windshield, evry 10-20mi some times, will have a long turm positive impact on FE

Wipers no longer ride high. They buffet badly, in constant motion above 45mph. Showing the previous owners use of a bug shield was a likely cause of the driver's side wiper arm having slop in the bushing. (The repair kit for witch is no longer available )

Sand kicked up off the lines /rumble strips (cuts on the shoulder to wake drivers) no longer sounds like standing in a glass box in a sandstorm. Sand strikes are not completely eliminated, but significantly reduced.
Side profile

As to how FE is impacted is unknown.
I also added the airdam 2.5"+2through 4"extension wile I was home. Pulled 23.83mpg 405.02mi via gps@70mph driving through a thunderstorm system front with 20-40 sustained/ gusts over 70mph head on wind so an air speed of 90-140+mph
Any losses I fill are still a gain, in reduced maintenance cost. And body damage not suffered from compromised visibility (moose make big expensive dents).
Dreem big chisel down to reality