Bantams boss Bryan Robson offered no excuses as his side slumped to joint bottom with Wimbledon after failing to score for a fifth successive game.
"This is the hardest management job I have had,'' lamented Robson. "We have been unlucky in some games but there were no hard luck stories today, we were well beaten.
"Sunderland wanted the ball more than us, but we have to pick ourselves up starting against Coventry on Sunday.
"The players know where they stand and fortunately we have experienced players like Danny Cadamarteri and David Weatherall coming back and Alun Armstrong is joining us on loan from Ipswich.''
Robson will need all his management skills, however, if he is to mount a successful survival campaign as the Black Cats roared to their biggest home win of the season.
Jason McAteer opened the scoring in the 44th minute with a brilliant strike, Tommy Smith increased the lead with his first goal for the club in the 67th minute and substitute Kevin Kyle completed the rout in the 82nd minute.
Bradford were left to rue two misses in the space of a minute midway through the second half when Mart Poom made excellent saves from Ben Muirhead and Michael Branch before Smith put the game beyond their reach.
Marcus Stewart hit the post in the 26th minute and a Kyle header bounced off the top of the bar in the last minute.