After one year plus and visits to remedy my brake problem, Toyota service changed a valve that they felt was the problem. It was not. I took it to arbitration, which at that time, the technical people gave me a full explanation of the brakes design. And, admitted that all prior service work done was a waste of time due to the brake design. The brake pressure is proportional. To top it off, the Toyota experts indicated that if I had the traction control option, things would have been different with the brakes. In the 2010 model they all have traction control as standard. I guess Toyota dealers were unaware of the importance of traction control on the 2009, they did not stock this option.