Automatic Transmission Cooler problems of the 2000 Chevrolet 1500

Hi I was hauling debris from my yard and taking to land fill. About 800 to 900lbs total. Stopped at convenience store for gas and food. Pulling out of parking lot, brakes gave out, brake pedal went to the floor. No warning lights. No warning at all. . . Barely any brakes at all. I was just about to get on expressway?? wow! there would have been no stopping this thing in an emergency?? I see gm already knows of this failure. I think a heads up would have been in order??? I've called all the people I know with similar vehicles. Only one person was aware of the issue and he has spent over a 1000. 00 in repairs. Replaced rusted brake lines. He told me he just replaced the transmission lines also. Has anyone been injured or killed?? I called the dealership, jerry's Chevrolet for information. I purchased it new. Waiting for service department to return my call.