How hard is it to change front pulley's???

[srkpaco]

I have a 2004 LC, I have done some searching on this site and I think I know what the problem is. I have a whinning right in the front of my engine in the mornings, i think it is the serpintine pulley or the tensioner going bad.

How difficult is it to replace these?

 

[APKhaos]

Not difficult at all. Suggest you remove the fan and shroud which really makes things easy to reach.
Check that the tensioner is OK. You may only need to replace the tensioner pulley [available as a separate part]. Download the FSM to read through the details of this job.
Try Sam at Lowe Toyota for a great deal on the parts.
You need to add a signature [UserCP] with model and miles. but assuming you have 100K or so on your 2004 a new serp belt and pulleys should quiet the noise. Mine sounded like a bad garage band every cold start