Streamlining - Wind/Air drag on Sprinter

Our Sprinters (NCV3's) push a lot of air at highway speeds. Has anyone tried any streamline work to reduce the air drag and hopefully improve fuel mileage? I can't help wondering if there was some way to improve the aerodynamics, especially the flat back rear end area??? Any ideas?

There are these here...

https://sprinter-source.com/forums/showthread.php?t=2768


I would think the biggest bang-for-the-buck on fuel savings is adjusting your driving style, but it would be interesting to hear what others have to say.

Sprinters are rather well designed from an aerodynamic standpoint, those roof channels aren't there for pretty. I know one person who installed Airtabs. He says it increased his mileage about 1 mpg and improves handling. They do not, however, help keep the rear cleaner.

Add my vote for the Airtabs. I haven't had them on long enough to be 100 percent sure but I am seeing a 1.7 mpg improvement. Biggest benefit has been very increased stability!!

piper1 said:

Add my vote for the Airtabs. I haven't had them on long enough to be 100 percent sure but I am seeing a 1.7 mpg improvement. Biggest benefit has been very increased stability!!

Click to expand...

Pictures please

yea we need pics

Here is a pic of a sprinter with the airtabs (from the airtab website)

My Scangauge II has a LOD function that provides a relative measure of the engine load being used at any given speed, grade, etc.
I would think a person could make a Sprinter test run at 65 mph for a mile on a level road in still wind conditions and record the LOD reading. Then install those Y shaped vortex generators to the rear edges of the Sprinter, and repeat the same test run and get a lower LOD reading... to see how much these things actually reduce the drag. Does this sound like a valid approach?