IMO in the US both public transit and fuel for passenger vehicles are subsidized. If you charge driving based on the cost per miles, toll road, raise fuel tax enough, raise the public transit fares enough, so both traveling by public transit and passenger cars are self sustainable, we'll get the following:
1) People decide to live close to work because both forms of commute would be prohibitively expensive.
2) There will be no traffic on the road, because when there is traffic, someone will either raise the toll so high or build a new road to compete, that there will be no traffic.
3) There would be privately run mini-bus that takes 16-21 people at a time on fixed route, as well as slower and cheaper big buses that runs on a less frequent schedule.
4) 2/3 of all auto plants, domestic and foreign, would file for bankruptcy, and the values of oil companies would fall by 1/2
5) No more SUV because the fuel + road toll would be $20 per gallon, like the rest of the world.
6) No more suburbia living, because traveling is so expensive. People would live in 60 story high rise to reduce transit overhead (see Hong Kong and Tokyo).
7) We would plan out trip very carefully, just like the way we would when we are traveling by air right now.
8) For those middle class who want more mobility, we would buy moped, bring it into our elevator when we reach a building, and park it in our balcony, closet, hallway, or our mini-garage in the apartment complex.