Squeak/squeal i can't diagnose

I made a thread months and months ago about a brief squeak i heard when letting off the brakes, i figured it was coming from the drums and i just needed to grease the backing plates. Well, i never got around to doing that, but i've been realizing lately that i cannot tell whether it's coming from the front or the rear.......guess i need to check it.

Is there anything that would make disc brakes squeak like that when letting off the brakes???

The separate squeel i'm getting now only occurs when the motor is warmed up to op. temp. but i can't tell where it's coming from because it won't do it when i'm idling. The belt tension is good, belt is good and not glazed/cracked, no fluids dripping on belt...............so i was hoping that maybe the shoes were dragging on the backing plate or the drum and i could fix that when i grease the backing plates.

This is really annoying, any advice or insight would be great.......thanks 2001 4.0

chek the idler pulley for your squeek while hot.

i thought about that, i lubed some of the bearing on it last time i took the belt off (like 600miles ago)

if it squeals can i just lube it up and it be good, or is it just better to replace it?? i know they're cheap

replace. If it's squeeling then the bearing race may be damaged, in which case it's just waiting to fail completely, and probably at an inoportune time.

could i just replace the idle pulley bearing??

if that doesn't fix my squeel, what else should i look at??

i know ya'll don't like bumps, but anyone else??

U-joints?