I think you only have 1 day to spare, at most.
Greetings, Nor, and welcome to the forum!
Maybe I'm just missing it, but I don't see Yosemite on your itinerary. It looks like you're going from Grand Canyon straight to San Francisco, right? Or were you planning on swinging by Yosemite on the way to San Francisco?
If you're just planning on going from the Grand Canyon to San Francisco via the quickest route, you'll be traveling about 800 miles that day. It can be done but it's a long day....probably about 14-16 hours (depending on what kind of traffic you hit). I think there's enough to see along the way that you should plan on splitting this up and doing the drive in 2 days. Barstow and Bakersfield are on either side of the half-way point and would make a good place to stop for the night. I would choose Barstow just because it's a fun, little town.
If you were thinking of swinging through Yosemite on your way to San Francisco, you might want to use the search function as there have been lots of discussions about this route lately. I'm not familiar with it personally so I really can't help you there. But I believe that you might find the passes still closed at the time of year of your trip making this option difficult, if not impossible. Hopefully someone knowledgeable about this will chime in.
Personally, I think your trip sounds great. Ambitious but not so ambitious that you'll be totally zonked from fatigue. If you allow yourself 2 days from Grand Canyon to San Francisco, you'll have one unplanned day. You know what I would do? I would just keep that day free. You might decide that you want to spend an extra day someplace and then you'll have that day available to plug in there. You might decide you need a day to just lay around by a pool or something to recuperate from the pace of your trip, and then you'd have it.
Anyway, that's my 2 cents on that.
Have a great trip!
