How often do the struts need to be replaced on the 04 2.5t S60?

 

Depending on where you put the bulk of your miles (city vs highway driving) they will probably start going South after 70-80K miles or 5-6 years. But they can go much sooner than that.

 

My car has about 37k miles on it 2004, and I do both city/highway driving on my way to work,but the streets where I drive are crappy.

 

How do you determine if the struts need replacing or not? The car had 85k miles on it when I got it, so I have nothing to compare it to.

 

A couple of tests you can do:
Driveway test:
When cars used to come with steel bumpers you could jump up and down on the front bumper. If the front was still bobbing up and down after you stopped, that was bad. What you can do instead of jumping on the bumper is press down with a lot of force over the front of the car. But that is a little harder to do if you're not a big person.

Visual test:
They sometimes leak fluid down the body of the strut. If it is leaking, its a dead giveaway that it needs to be replaced. Worn shocks won't necessarily leak though.

Road test:
I like the drive test. Bad shocks or struts can make the car exaggerate bumps, dips, and potholes. New cars will hug the road on dips and bumps, and won't deflect much at potholes. I noticed with bad shocks and struts that expansion joints would cause the car to hop and become unstable.

It is a good idea to check other components before or during strut replacement. Also, always replace in pairs whether it's shocks or struts.