I saw a 40ft Dp going over it one day.......but I wouldn't recommend it, especially towing a vehicle......to many hairpin, blind corners. I was raised in the area. I remember an 18 wheeler took the route by mistake. The driver thought he was going to die. Also helped out a pickup towing a trailer that was 1/4 mile from the summit on the east side and was spinning his tires. We managed to use a couple of other vehicles chained together and helped tow him up over the top. There's warning signs about the 26% grade. I'd take 88, much easier and safer drive. Sonora Pass is beautiful, but in the right vehicle.
Brian