A few times while traveling at fwy speeds, as we start to go uphill the car violently shakes back and forth (steering wheel hard to hold on to). vsc, trac and the liitle car with the skid marks behind it flash on the dash along with an alarm that lasts from 3-5 seconds. we have had a hard time keeping the car in the lane. almost ran into the center divider. we have taken it to our personal mechanic, called toyota, taken it to toyota of san luis dealership and nobody has been able to find the problem. it is in our opinion that this car in unsafe to drive and unsafe to sell.