You have gotten a lot of good advise. I did the “Take four years off from school & explore America” thing just out of high school. It was a blast & I learned a lot about myself. I also learned about the folks that make up our country, good folks for the most part. I recommend a trip like this to many young folks.
Are you crazy for doing this? No, not for doing this. You may be crazy for other reasons that we are not aware of. Just not for this.
Is it safe? That depends on your definition of safe. You will probably not get robbed or killed by criminals. If your rig is in good shape, your chance of breakdowns is very low. You are more likely to get in a car accident because you are very tired than almost any other cause, not counting drinking & driving, of course.
Is it doable? Of course! Folks have been doing this kind of thing ever since the automobile was invented. It was much more dangerous then.
I also second or third the idea of slowing down & truly seeing the sights. If it takes you more then a week to get to Oregon, is it the end of the world? You will be learning about our great land, as well as about yourself. That last can be scary.
The thing I regret about my four year “vacation”, is that I did not slow down sooner to see more of this country.
I will recommend using “Blue Highways”, the two lane blacktop highways that go through the small towns, instead of the freeway that by-passes them. You will see more of America that way.
While Stranger On A Train’s advise is good, he must have forgotten about the hundreds of miles of interstate freeway out west here, that literally have no services. The highway department usually puts up signs to warn about these stretches. If you have my luck, some fool stole those signs. Keep the fuel tank full.
Oh, Do not count on cell phone service every where out here.
Look on traveling forums to determine what you should bring with you. For the long stretches of road, out west, carry two gallons of distilled water in the trunk ($0.75 a gallon at wally world). If you get stranded, (not likely), you will have water for your radiator, your battery, & drinking water. All in two, one gallon jugs.
IHTH, 48.