Brake Foundation Components problems of the 2005 Mazda Tribute

After the 2005 Mazda Tribute is highway driven for 4 to 6 hours the brakes fail to stop the car within normal distances. It feels like there are no power brakes; much like stopping 1960's cars with drum brakes. These failures, do not occur in around town driving; and cannot be duplicated by the Mazda dealership during around town test drives. As it only occurs after the vehicle has been driven for hours, and particularly in hot climates like arizona, it appears the problem is heat related. When trying to stop exiting a freeway, and standing on the brakes, and still blowing through a stop, it scares the hell out of driver, passengers and other traffic and has the potential of being lethal to persons and property.