Sonoma's pavement is worn out. It needs a repave badly. Turns 4, 7 and 11, all tight, and very low speed, (50mph and below) corners which where very slippery. New tires for a few laps was fine. Also lots of cornering while on throttle, ( turn12, 1, 5, the esses) That puts a lot of energy into the tires. And on a big heavy, under-tired car was not a good mix. If we had run the Indycar/PWC layout, things may have been a little better as that pavement, and the traction areas were not as worn out as the "standard layout" places.