Are these a drag, or what?
 

I have four of these, one behind each wheel. Seems like a little cup to capture air. But is it helping airflow past the wheels somehow? Are these a drag, or what? :confused:

put them on the front of the fender to deflect the air around the tires

behind the tire=drag, in front of the tire=helps divert airflow around tire.

I could be wrong but I think those are some kind of splash guard to save the paint behind the wheels from excessive wear and tear.

Thanks all. I took the two behind the front wheels off easily, but the rear ones will have to wait for the jack and better weather.

you are absolutely correct. If you drive through a ton of gravel or lose sand frequently. It is the standard automakers "one size fits all" approach. Removing them is on the 65+ mods to better efficiency. numerous people have seen improvements from doing so.

Took mine off my Jetta and noticed an immediate benefit to FE... went from averaging ~58MPG on my daily commute to ~62MPG

(Note: This was not controlled A-B-A test, so other factors may have contributed to the difference in FE)

I remember reading in Popular Science (or Popular Mechanics) in the late 90's about the new VW Polo, and it said something like Cd=0.32 (0.34 with mudguards):eek:

We are currently Diesel Jetta-less which is my intention to remedy. I do remember how sometimes I would simply forget to fill up since I could go over six hundred miles on a 12 gal. tank of fuel. :) Amazing car, fun to drive.

For those who worry about their paint, there are polyurethane coatings that will blend in with the color and protect the finish. Just apply them where the mud spray hits. Works like a dream.

T-9020 is the part number from Trim-Brite for a clear film that can be applied. If I had a vehicle with paint worthy of concern, I would wrap the rockers,hood edge, and possibly the front end with this clear film, to protect.