Hello,
If you're leaving LA on a weekday then you'll want to leave early to avoid city traffiic. It's not clear if you're thinking of going to Yosemite as a day trip from San Francisco. It's a long drive with traffic in Bay area so you'd want to spend at least one night close to the park or in the park. Finally, I've seen other postings on this website indicating that you might not be able to use chains on a rental car. You won't need chains in cities, on interstates or along coast.
Jessica