idler pully

Hey y'all, I use this forum all the time, most recently for a weird squealing noise when idling after going through some mud. After some research on the forum I saw that many people had this same problem and ended up having to replace their pulleys. I went to Rock Auto from a link on the forum...

2007 6MT ~95k....had just finished installing new LED lights on front end, and started it up and noticed a faint but definitely audible whining sound coming from the front of the engine bay, also audible in the cab while idling and driving at low speeds. Not sure if this has anything to do with...