I never ran into check points on 89, but they do close 89 at Emerald Bay when it dumps. Most rental agencies are more williing to rent a 4WD than to provide chains (they claim chains damage suspension, which is true of some cars; it's just a better deal for them: 4WD is more expensive to rent). A couple of times I saw people being turned around on 50 if they didn't have chains or 4WD with snow tires. In March, we usually get a final dump storm around the first/second week of the month. Not as heavy as in the winter, but more slick (wet snow).
Sometimes I wonder if chains would not be a better solution (better ice traction), but keep driving my Subaru: got too lazy lately to get out of the car in the middle of nowhere and - usually - in the middle of the night [img]redface.gif[/img] Especially so when driving up the Alpine Meadows road: NOT the most pleasant drive, but the place is worth it.