Most people think you lose breaks becuase a hose busted or something like that not got hot... that trucks brakes were not hot enough to be steaming or smoking so they were still functional.. It looked as if the truck was swaying he tried to correct it without realizing he was about to fly through an intersection.. my guess would be he was distracted driving at first... wondered out of his lane.. tried to correct but was top heavy with a loaded drum as he was accelerating down hill and a curve at that and didn't see the stop light in time.

Also there is no way all six brakes cammed over at the same time. The truck didn't even attempt to stop.

Source: I manage fleet of over 200 trucks for one of the larger concrete companies in the south eastern region.