I've done this. When I was 17. 21 years ago.
It was my father & mother. My sister and her fiance. My grandma. And my best friend. In a Ford Aerostar. Yup, it was tight. We did have a car top carrier.
But it was amazing. As I recall, we took 2.5 weeks is all. On the way out we took the southern route (we live in southern Ohio) through St. Louis. Then zipped through Oklahoma and Texas. Our stops were at the Grand Canyon, the petrified forest, Joshua Tree, Death Valley, Sequioa, Kings Canyon, Yosemite, San Fransisco, Monteray, San Diego, Oceanside (we had friends there that we stayed several days with), and LA. Not in that order. We didn't visit Disneyland
. On the way home we did a northern route through Denver (we didn't stop.)
It was a whirlwind. But it was on that trip that we discovered my grandma had cancer. She died a year later.
Since then I've driven to Yellowstone from here, that's the longest. I had no desire to continue to the west coast.
And I love road trips.
I'll tell you this, the entire way out we were all in serious road trip mode. So relaxed and happy and just a delight. Once we turned to home, we drove nonstop. Literally. Not even a McDonalds. We just ate from the cooler and gas stations when we filled up. It's been a long time but I think it took us 36 hours straight. The only thing I've ever done that was more grueling than that was my flight home from Moscow Russia. THAT was exhausting.
But that drive home, OY! My dad and I were just talking about it the other day and that only his utter exhaustion allowed his nerves to relax enough to sleep while I, his 17 year old daughter, drove through a snow storm with road construction in Rockies from midnight to 5 am. And I did a good job too.
I wrote a trip report of our Yellowstone drive. It might give you a good idea. Just add on an extra 1,000 miles each way. It's still active on the Trip Reports on this board. Something like 4,000 miles of love? It was several years ago now.
Would I recommend it? Of course. But not for everyone. I'm a chill, well planned but go with the flow person. And I love adventure and scenery. I have an excellent relationship with my dh and parents and sister and her husband. And I organize people and keep the peace for a living. So I can't say I'm normal. And my kids aren't normal either. They inherited the chill attitude of their dad and I.