Hi,
I took the car for chaning oil and maintenance and the guys told me that the there was something strange with the front air suspension. They took out it from the car for inspecction and found this:


They say that I need to replace the full piece and that it is really risky to drive the car like this since these 3 screws are supporting the suspension. I´ve been investigating and watching some videos in internet and I saw that it looks it is not needed to replace the full piece, just the air box, and I think that these 3 screws are not supporting the suspension, they are just somehow fixing it to the car. To be honest, I´ve been driving the car for long and never notice nothing strange with the suspension.

what do you think guys? is really needed to replace everything?

 

Yeah there is nothing holding the top of the strut to your car. The top plate does not come with a new air bag so you’ll have to get a new strut, or a good used one to take the top plate off of; or weld in three new rods. There should be three threaded rods on the top plate; sticking through the upper strut mount, and held fast to the fender by nuts. You have none of that; it stay reasonably put under serious compression but you’re lucky this didn’t collapse or bang around while driving.

Edit: a new arnott a-2575 air bag comes with a top plate, so all you would have to do is to swap the bag over per the video below. I should have known this, as I just did this job a few months ago! You'll need a air ratchet to DIY this properly - if you're having someone do it for you, just buy two whole new struts.

 

Those three missing screws are the ones that hold the upper side of strut to the car. You can replace just the air spring, see this link:
I would replace the entire strut based on the age of the car. If you buy from Arnott, they offer life time warranty so is more beneficial to replace the entire strut and have the warranty for it. There are other sites, like FCP and eEuroparts that also offer life time warranty and have other brands, including Genuine Mercedes parts. And I would replace both struts. When one fail the other one tends to fail almost immediately.