1997 Dodge Ram poor fuel economy, runs rough/shakes,underpo

I have a 97 ram 1500with the v8 5.9lt gas engine, i have noticed recentlly that i get alot of shake when im driving, my fuel economy has drasticlly reduced, and it seems to run rough and be underpowered. i recently had my fuel pump go out while driving and had it replaced as well i replaced the spark plugs and wires. it seems to happen the most on my way home from work around 2 when its hotter but it does it in the morning sometimes as well at 5am. please help if you can