We have made 8 trips in the past 7 years. I have not found any damage to the truck outside of small stone damage to the lower part of the trailer from stuff tossed up by the drive wheels. I have had greater damage on the Interstates and Federal Highways from thrown debris and unmarked chuck holes. I would guess that puts me at about 48,000 miles to and from. Others such as joe b and sue t may have a lot more miles and experience, but I have not heard them doing anything special.
We still see some units with all sorts of nets and frames and such draped over the fronts, but it is not 1964 any more. Enjoy the trip and don't worry about it.