1997 Chevy Truck engin misses

Engine Mechanical problem
1997 Chevy Truck V8 Two Wheel Drive Automatic

i have a 97 chevy 3500 7.4 vortec, it acts like it loades up at a red light. When u go to take off it hesitates. It also while driving u can feel like it misses or cuts out no bad but u can feel it. The other day the ck engine light came on so I took it to my local gm dealer and they told me it wa the o2 sensors. But they reset the comp and it runs fine. They said it was my fuel pump losing pressure when key was off, it pressure was fine while it was running. They also said it could be my egr valve. I need some ideas, I went and got my truck and it still acts like its miss fireing and cuts out on the way home. If u sit still with truck in park and give it gas it cuts out or misses till it get to about 5 grand. I need help with this.