I was wondering if the pulleys from a s4 alternator and s5 alternator are the same?

 

yes

 

I find they are not. The shaft on the series five is a larger diameter so the S4 pulley won't fit unless the S4 pulleys hole is drilled larger to fit the series five.

 

okay so how easy is it to remove the pulley? are they just pressed on?

 

its a lot easier to use an impact, if you have the alt mounted you will probably not be able to get it off without breaking something, at least with my experience

 

If Banzitoyota says there the same ..............then I'm probably mistaken in what I wrote. But that's the way I remember it. Let us know how you find it when you get the pulley off. Trying to see how I got that wrong.