Ok i put on a bassani cat back and took it to a straight road down from my house went WOT and dang did it run good. Turned back around and did the same. Ok at about 120mph i slowed down and turned around and noticed what sounded like it was missing alittle. Went to the house and it idled really rough like it wanted to die. Truck is sluggish and sounds like its missing when im getting up to 70 or so but when i get there and set the cruise it seems to run good. Anyone have any ideas. I think its either fuel filter or something just havent got to check yet please let me know.

Thanks

 

All stock with exception of a catback? Did you let it shift into OD @ WOT? Sounds like you damaged a plug. Pull the plugs and see if any are cracked or have missing peices!
You might of poped off a vac line. Check the one on the lower intake on drives side towards the front.

 

Yea its all stock expect the new exhaust i put on. Could i have pulled a gas line lose from tank when i jacked the rear end up putting it on. I did it on the ground without a lift. If so would there be any leaking on the ground.
Also i have to pump the gas to get it to start sometimes

 

It def sounds like a cooked plug or vac line to me
GOOD LUCK

BTW,
Hows that Bassani sound ???

 

It sounds freakin sweet

 

How many miles are on the fuel filter?

It doesn't exactly sound like a fuel filter problem, but I wouldn't rule it out, and its easy to change (and cheap), if you want to test that possibility.