So I've been on this road trip all day. Still got about 300 miles left but I'm getting a nice little break in the passenger seat. On again off again all day I've been trying to think of a good way to describe the drone, just something to keep my mind busy. I think I finally got it! With the windows down it sounds like when you blow on the top of an empty glass Coke bottle. With the windows up it sounds like Chewbacca groaning at Han Solo. At highway speed it's particularly bad between 2000 and 2500 RPMs with any throttle
Do a J Pipe