Engine noise

[stx Ryan]

Hey guys i could use some help here. I was driving my 05 4.0L sport this morning and noticed an odd noise coming from under the hood. Its not very loud, the best description i can give is it sort of sounds like an electric motor running. Im thinking it was something to do with the belt or maybe i have a bad pulley. Anyone have any knowledge of this issue? The truck does have 240k miles on it.
Thanks

 

[stx Ryan]

Update:
Got home and it sounds like its a water pump.
And sorry just realized this should be in maintenance

 

[PinkTaco]

Is it overheating? Should if its water pump

 

[sfstud2002]

Check your power steering fluid.

 

[stx Ryan]

I changed the water pump, however the noise is still present, power steering fluid is fine, maybe the alternator? The noise is coming from the drivers side of the belt assembly, so either the alternator or the ac compressor.