There are several discussions regarding Innova alternator matters so I thought of starting a new thread to address those issues.
Please view the pictures of the Denso alternator unsed in Innova at FB "Toyota Innova Owners Phils". Those picture can be helpful.
My alternator developed strange noises at about 100k km. All that was needed was bearing replacements (2 pcs) which cost me just P500 labor and about P200 for the parts. I can't recall if I changed brushes as well but they are very cheap. It has since run about 75k km more without any problem.
It's a 30-minute job so the labor is quite reasonable.
I hope this answers some of the questions.
Cheers!