2006 4runner, help diagnose this sound Please!

[chillaxing]

hey guys can you help me out with this sound. I though it was the fan clutch at first but further inspecting it sound like like it coming from the alternator area.

everthing runs ok except when i'm hitting the 25-30 mph area, then it run a little rough till I pass that speed.

Don't know if the video will help.

This is from a cold start, if more vids will help I will upload more.

https://youtu.be/W-OhojpTO8s

 

[Morphyne]

Well, it sound like either something is loose or you have a rod knock.

Loose = cheap fix
Rod knock = not-cheap fix

one way to diagnose a rod knock is rev the engine and if the knock revs up with the engine, you are looking at some serious engine work.