i have 2005 s 60 where is the cabin filter and does it need any special tools

 

It is under the dashboard in the passengers footwell. No special tools needed. You may need some advil afterward for your contorted back, it is not the easiest place to get a human body into.

Directions with pictures:
http://www.boschautoparts.com/NR/rdo...stallation.pdf
See page 64.

 

A quick search on the forum came up with several hits.

The most informative were: https://volvoforums.com/m_30244/tm.htmand https://volvoforums.com/m_63315/tm.htm

The model years are different but the info is applicable to yours.

You need torx keys.