Weird idle feeling and sounds

Hey all, I have noticed an odd sound and vibration whenever I have my truck (04 DC 4.7) in drive and stopped at a light or something. It happens with the AC on and off, it’s also sitting at 550-600 rpm when it happens but in neutral it’s not there same with park it’s lighter in reverse. Any tips or recommendations are appreciated!
Thank you

 

Have you checked your transmission fluid level and appearance/smell? I would start here. The next suspect would be the torque converter flex plate, but let's start with the easy stuff first. You didn't mention mileage or what, if any, maintenance has been done. Need a little bit of history...

 

2004 DC 172k miles, new denso coil packs newer plugs, timing belt done 2000 miles ago, lbj done last week. Shifts fine but has recently started idling funny in drive it’s also 4wd

 

No CEL? Have you checked?

 

It occasionally pops a minor evap leak code which could be the issue but I suspect that would affect idle at all times. I’m just too lazy to put a smoke machine on it

 

2WD or 4WD? Kinda important bit to share.