I would like to change the coolant in my 2006 Volvo V-70 as I had to add about 2 lires of ordinary water in it (loose coolant reservoir cap),
Can one do it oneself and if so how?

 

Yes, I recently did it for my V70. There are several threads under the V70 and S60 sections on DIY coolant changes.......the engines and transmissions are the same on these two models from Year 2001 and newer. Do a Search under Coolant Changes and you'll bring these posts up.