hi who can help me again I have a 2004 b3000 and this is what is happening if its very cold like way below zero or very wet roads and raining my brakes lock very easy I think its the back brakes but not sure , this problem is a real pain in the *** and also very dangerous on icy roads ,truck is standard but I still have to use brakes a bit to stop , so far no mechanic has fixed this for me yet ,please HELP