I'm thinking fuel pump as well, but we always start with the easy stuff first. First a scan to see if any diagnostic trouble codes lead us to a possible fix. After that you can determine if it is a fuel related problem by having the fuel pressure checked. There is also a device called a fuel pressure regulator I want you to check, but I am looking for pictures of your engine so I can show you where it is. Once you locate it, there is a rubber tube going to it you can pull off, and smell inside the tube to see if it smells like gasoline. If it smell like gasoline, the fuel pressure regulator has failed.
Do you know what size engine your truck has?
2001 Bonneville SSEi (retired at 365,000 Kms.)
2014 Jeep Grand Cherokee Overland (yes, I know its not a GM)