We just experienced the best tail-wind ever about a month ago. We were traveling from the West going East along I-40 with 60 mph gusts. It was literally pushing us eastward. Otherwise, I would not want to drive into a 60 mph headwind....... mainly for gas mileage!
There were two full days of winds where we traveled 750 miles at about 55-60 mph. I averaged 9.1 mpg on that tank at just over 1,100 miles total. At 55,500 lbs., that is quite nice!
We don't seem to be too affected by heavy cross-winds, we certainly have to be aware but I've never been blown around too much to feel dangerous. We are fairly rock solid.
MM.