I originally purchased the AeroShield Model WD600 on my tow vehicle because I was getting hammered with bugs on the nose of the RV, and it just was a pain to keep clean. So I ran across the AeroShield that made the claim that it all but eliminated bugs on the RV.

It also made a claim that the fuel mileage would also increase. I am a bit skeptical about all of this, but since virtually every semi-tractor/trailer has some kind of aerodyamic shield on the cab, there must be some truth behind at least the MPG claim.

It used to be that these things were pretty common for RV'ers that towed big 5th wheels, but you don't se a lot of them anymore. Perhaps it's because the noses of modern 5th wheels are more aerodynamic, or perhaps other reasons. My primary goal is bug-proofing, but if I also get better fuel mileage, so much the better.

There are four models of the Aero Shield; white or black, and for mid-size or full-size pickup trucks. I went with the black full size model for my 2016 GMC 2500HD pickup.

The Aero Shield attaches with suction cups to the roof, assisted with straps that grab the drip-rail of the doors. I am a bit nervous about the straps though as they could mar the finish. I did add some rubber strips under the straps to hopefully keep that from happening. The shield also weighs around 20lbs so you can remove it when not needed.

I did notice some wind noise when not towing, and it seems the fuel mileage when not towing is reduced a bit - which makes sense as you are actually adding a bit of drag to the vehicle. But compared to the drag when towing, the Aero Shield should reduce overall drag.

I also noticed that when towing, air is getting trapped between the cab and nose of the RV, as I have found things get sucked out of the truck bed when towing if they are not really secure.

Therefore I have to conclude that trapped air must increase wind resistance, thereby reducing fuel mileage... at least that is my theory; and I am sticking to it.

The manufacturer claims a 3MPG improvement. If that is anywhere close to accurate, that would result in a whopping 20% improvement. I find that a bit hard to believe. A 5% improvement I could believe, but 20%?

Still, you see this concept on most semi's, so there must be at least some benefit. So we shall see...

My first test consisted of about 40miles on the freeway at 65mph. I used my vehicle's built-in fuel mileage gauge to determine what the result is. Even if the gauge is not totally accurate, I have to believe that since we are looking for a change, any error in the gauge would be replicated in both the baseline and change results, which should cancel the error out.

I typically struggle to get 13MPG, and have typically averaged about 12.5MPG in the first two seasons of towing. But after the first 40miles, I saw an incredible 15.5MPG! And that is a 20% improvement. However, I must do another test round-trip. Ideally this would be under the same weather conditions; temperature, wind, humidity, and traffic conditions.

However, it wasn't until a week late that I was able to return. I was kind of surprised that on the return trip, I averaged 12.2MPG, which is less than I typically get. But the weather was different on the return; it was raining. And there was a construction zone in the return lanes that was not in the outbound lanes. This resulted in changing lanes and running at different speeds.

So I am not sure how well of a test this was. Even then, I saw a 1.3MPG improvement, which is about 10%. So my initial conclusion is there is indeed a fuel mileage improvement, whatever that may be.

We plan on at least 4,000mi over just 3 trips this summer, so I will keep a spreadsheet on the mileages and post on this website as the data comes in. Note that I am only calculating highway miles as that is the only time the Aero Shield is effective. So if you check back occasionally, you might see a more accurate result.

Part numbers: According to the manufacturer's website, the following part numbers are for the 4 different versions:

• 01217 - Black WD600 (56"x22" - full size tow vehicles)
• 01508 - White WD600 (56"x22" - full size tow vehicles)
• 01216 - Black WD500 (48"x22" - mid size tow vehicles)
• 01546 - White WD500 (48"x22" - mid size tow vehicles)