Turns over but will not start?

You actually descried the two common failure modes, but one relates to GM fuel pumps. When Chrysler pumps fail, they almost always fail to start up, leaving you sitting in the driveway or parking lot. If they do start running, they rarely quit while you're driving.

GM pumps fail in the opposite way. They almost always start up, then either stop or slow down while you're driving, leaving you sitting on the side of the road.

A dead Chrysler pump can often be started by banging on the bottom of the gas tank. When that works, it's going to happen again, but it could be the next time you try to start the engine or it could be months from now. Over time those failures get more frequent. That type of failure is due to worn brushes inside the pump's motor.

The first thing is to listen for the hum of the fuel pump. You should be able to hear that for one second when you turn the ignition switch to "run". If you hear that, the pump is working. The better suspect then has to do with the dead or run down battery. When that happens, or it is disconnected, the Engine Computer loses its memory. All of the sensor personalities and fuel trim data will be relearned as soon as you start the engine, without you even noticing. The one notable exception is "minimum throttle". Until that is relearned, idle speed will be too low. The engine may not start unless you hold the accelerator pedal down 1/4". You won't get the nice "idle flare-up" to 1500 rpm at start-up, and it will tend to stall at stop signs.

To meet the conditions for the relearn to take place, drive at highway speed with the engine warmed up, then coast for at least seven seconds without touching the pedals.

If you still have a crank / no-start condition, the next step is to check for spark:

https://www.2carpros.com/articles/how-to-check-for-ignition-spark

Loss of fuel accounts for only about three percent of no-starts. Loss of spark another two percent. Most no-starts, the other 95 percent, are caused by a loss of both fuel and spark at the same time, along with the loss of injector pulses. We can discuss that next if necessary.

Let me know what you find.

You sir are a wizard!! I did everything you said to reset the computer's memory and the truck is running perfectly just like it was before. Thank you for saving me at least $200.

Actually, I only know three things, and you asked about one of them. I'm very happy to hear you solved this. Please come back to see us with your next problem.