Since you have a newer truck than mine ('98), you also have "Coil On Plugs." If one is bad, you may get the same symptoms, where at higher engine RPM, the engine seems to compensate well - but not at idle. Just saw that with my stepson's 2006 Crown Victoria. Got a code reader, showing Cylinder 3 misfire. Got one off a wreck to test the theory, and that fixed it! Go to an auto parts store, and let them check it. If the coil is bad, it'll show up immediately.
1998 SuperCab Lariat, K&N CAI, LED Halo headlights, LED gauge / temp / headlight switch panel mods