I want to change the power steering fluid in the C280. Do I need a filter? And from the archives I ntoiced that I should only use MB Power Steering Fluid. If I do need a filter, how hard is it to change? ANd how hard is the fluid to change? Is it as easy as siphon and refill?? How often does it need to be changed?

It is easy
 

make sure that the tube that you stick down in there is clean. Replace the filter and use MB fluid. Once you suck out the fluid you will see the filter. Unscrew the nut (it is spring loaded) remove/replace the filter and screw the nut back down.
Jim
'85 300D
'95 E320
'97 CRV

THanks Jim. I am going to do it this weekend.
Does anyone know how often it needs to be changed?

one other thing
 

I would fill it, install the cap, crank up the car and move the wheels from side to side. Suck out the fluid that is now in the reservoir, refill and do it again. I did this about three or four times until what I was removing looked clean. This will allow you to get the fluid out from the hoses, etc.. I would recommend doing it about every 30-40k miles (about the same schedule as brake fluid).
Jim
'85 300D
'95 E320
'97 CRV