GM-GMC: 2002 silverado, fuel pressure gauge, chevy silverado

Question
I have a 2002 chevy silverado 2500hd 4x4 with 6.0 engine 115,000 miles.  about a year ago fuel pump and fuel filter were replaced truck ran good.now truck will run and die. i replaced plugs truck idles ok when you drive it, it accelerates normally when you drive it easy. when you go to get on highway and push pedal to floor it bogs down and wont get out of its own way.let off pedal it runs ok. what could be cause. thanks

Answer
Hmmm.  It is possible that the truck is starving for fuel.  What you would need to do is hook up a fuel pressure gauge and tape it to the windshield and go for a drive.  If you see the fuel pressure drop when you want power you can be sure you have a fuel problem.  If it doesn't drop at all your into something different.  That is where I would start.  Too expensive to just guess at parts anymore.
Hope this helps