Lots of studies on that kind of stuff. Tractor Aerodynamics – North American Council for Freight Efficiency This is a good start if you are interested.
For sure that helps but I am including the lifetime I have owned this truck. I have records on all of my trips and this was the best by far. Also I treat my fuel so it is not as bad through out the year. More issues with the cold then the fuel.
This dude has some interesting stuff, pertaining to cars. However, the basic principles pertain to anything. https://youtube.com/@JulianEdgar
Schneider did a test on the wheel covers and found out it is 1/2 of a percent per axle, so on a tandem it comes as a 1 percent gain in fuel mileage.
I will take a look at that later on and see if I can find anything interesting. I like looking at stuff like that as well even though I don't have my Mustang anymore.
From what I know, anything can be made slick in a wind tunnel, at 0° yaw. But, rotate the table to simulate a crosswind and things go south in a hurry.
No doubt about that as I had that happen to me yesterday driving in Iowa going back to MO. Went from 9.8 to 8.5 in a real hurry.
So this trip was the best overall MPG's I have had on a run so far. To recap I went from MO to MA at 8.7 MPG's running 70 mph or speed limit the whole trip with around 15K. Then went from MA to IL with another load that I believe was around 20K and got 10.1 MPG's. Then went from WI to MO with 38K and managed 8.1 MPG'S running 67 and would had been a lot better if I had not hit some mean wind in Iowa. That took well over 1MPG's off my trip coming back home. Total trip was 8.9 MPG's and best over all trip I have done so far. Honestly it felt like the truck has finally really broke in and of course the trailer aero has seemed to help as well. I also have the lift axle being ordered and should get that done in a few weeks or so. I will use that on some of the real light loads I get and dead head. Might regret it but can't help but want to try it out to see myself how it works. Even if it just works on very light loads or dead head it will be worth it in the long run. I have a bad attitude sometimes and get pissy and decide to dead head home from long miles away sometimes when I get sick of it. Ha Ha
You’re never going to know, unless you try. With you being an O/O, you’ll have better control, which means better potential of success. I still think Nose Cones are worthwhile, despite some discounting them on aero trucks. Again, in yaw situations, they have to be beneficial. Wind is rarely straight on.