2004 GMC Sierra 2500HD Rough Idle

[skier124]

So i cleaned the maf and throttle body and put half a can of seefoam in the pvc valve and some injector cleaner in the gas tank. It feels like its running better but still has a rough idle. the rpms are near 5 to 6 when the engine is warm that's when it shakes the most you can feel it in the drivers seat.
Is there anything I'm missing or should of done differently?

2004 GMC Sierra 2500HD 6.0

[searay220]

Plugs,wires,coils,injectors,fuel filter,fuel pressure all need to be checked.