I know this topic has been beat around but, I still do not know which brake to go with. Is there anyone out there who has driven a rig with a pac brake and one with the jacobs. If so is their a difference in the braking ability? I am hearing stories that the way the 03 cams are designed there is a ground spot which keeps the valves open a little longer and this is the reason a few people around do not think their brakes are as good as before. I guess one other question would be is there anyone out there who is not happy with the jacobs brake?