I covered Oregon and Washington for my sales job and did a lot of driving. At the outset, I would speed and confront other drivers. My mood was usually sour when I arrived at my destination. I changed. I drove the speed limit so I didn't have to look over my shoulder and was overly courteous to every other driver. When something happened I shined it on and didn't let it bother me. I found that I arrived at the same time and was more productive when I got there.
I do the same with my trailer in tow, relax and be courteous. Can't imagine driving 5,000 miles in a foul mood. After all, I'm on vacation.