I do a monster roadtrip just about every summer. I usually don't do a ton of miles in a day, but often get sick of being on the road and knocking out a ton of miles the last day. I have done a ton of marathon driving days while on trips. Just a few years ago I did roughly 1000 miles in a day leaving Las Cruces, NM to home in Papillion in a day. I took mostly highway instead of the much faster interstate so I could see some sights along the way. The stupid part was it was getting late in Kansas somewhere. I was nodding off and stopped at a gas station and powered up on Red Bull and continued on. I was doing about 100 mph up some highway into Nebraska and ultimately stopped at some truck stop in North Platte. I slept about an hour in my truck and thought I was good and hopped on the interstate home. I was probably doing 90 down the interstate knowing full well I was in no condition to drive. The drive from North Platte to Lincoln was a blur. The last hour I was awake and no problem. That was the dumbest drive I have done in a day.
While in the Marines, I did a couple drives that were longer. I drove my Monte Carlo from Sundance, WY to just west of Seattle in a day. Google says that is 16 hours, and about 1100 miles. I don't really remember. I had orders to San Diego a couple years later, and drove back with another guy. I had a stick shift truck by that time with a passenger who didn't drive stick. The second day of the trip, I did roughly 1300 miles from Missoula, MT to home in one day, and my brother drove us to Des Moines to drop my fellow Marine off. I still remember driving all night across the state of Nebraska. I stopped in Scottsbluff and drank some coffee and ate some grub. My buddy was a nut and we listened to Metallica and Stormtroopers Of Death while he told stories through the dark Nebraska night about how humans were born from aliens and stuff like that. It was awesome in hindsight. I will actually go see Metallica for the first time this fall in Lincoln.