AC Compressor or Idler Pulley Noise

[Diesel_Dog]

I've got a whine coming from my front end. Constant with the RPM's from idle up. Goes away (lessens) when not on the accelerator. Ive done some trouble shooting and determined that its either the AC compressor or the Idler Pulley (removing one belt at a time until noise went away).

The Bearing in the Idler doesn't seem super smooth, but I don't have anything to compare it to? When I spin the AC compressor it makes some noise, but again I'm unsure if it should make noise? Should I hear anything when I spin it free hand? (are the veins moving fluid?) Are there any bearings in the AC compressor that can be replaced?

I'd like to get some thoughts before I start throwing money at it. I thought I would start with the cheap (Idler) and work my way up. It sounds like the idler goes often if you wheel your rig?

Thanks for your thoughts / experience.

 

[kball]

The idlers are kind of known for going bad. I think they are pretty cheap too so I would definitely start there.

 

[2007toyota4runners]

I had this happen twice from mudding and it was the idler pully

 

[Diesel_Dog]

I've read that the idler goes bad. I had it stuck in a mud hole last weekend so I'm thinking that is what caused the problem (to hopefully just the idler).

 

[Diesel_Dog]

As an update I installed a new idler pulley and the noise is gone. When I ordered the new one from Conicelli I had two choices: dealer or factory installed. I chose dealer ($10 cheaper) and was happy to find that the bearing can be replaced. Now it's a $2 bearing to swap out vs a $30 pulley. Bring on the mud!