Great improvement by spraying undercoating in the wheel wells.
Just remove the tires, take out the 8-10 plastic screw clips and remove the plastic inner fender liner. Stuff some newspaper in the areas you do not want overspray, (springs, hoses, Struts etc) and Spray 1 can of rubberized undercoating in each wheel well, allow to dry for
1 hour or so and put it back together.
Cuts the road noise by 50% at least! Cost about 6 bucks a can, and about 30 minutes work,+1 hour waiting!
Very happy and quite easy!