I just had a rear air spring start leaking on my 2013 S212. It was going down in less than an hour so I didn't really have much of an option. The google-foo and youtube-foo regarding separating the spring from its seat in the suspension arm is all about how hard to hit it from below and with what size hammer. I gave that a go, quickly got nowhere. So I came up with another method. I used a gear puller to push upwards on the spring seat. It worked very well, and didn't involve very much cursing at all!

Here are some pics showing the orientation of the puller. (Obviously the spring is already out.) I put a 3/8 drive socket on top of the threaded rod to provide more surface area; it embedded itself in the plastic during the process but was fairly easy to remove after. Last pic shows the make/model of the puller I used, but there are plenty of manufacturers. If there was any trick to it it would be that the innermost arm was placed in its shorter configuration; again see pics.

I believe this is a pretty good method, for this reason: now that I have the springs out I can see that my suspension arms are very badly rusted in the area where the spring seats, so bad that I am replacing them. That's how tight these particular springs were. I hope this information helps the next poor soul who DIYs this job.

 

Oh boy. Rear spring arms are out of stock, with no ETA on when more will arrive. Reminds me of a certain battery I had some fun with not long ago. So, I dropped the pieces I have and descaled them to the best of my ability, tools, and patience. They're being coated with Eastwood Rust Encapsulator Plus as I write this; first coat is on, and I'll follow up with a second coat in a bit. Then back we go.

Adding a bit to the knowledge base portion of this thread: it looked to me as though the spring arm had a camber adjustment bolt at its inner mount point -- it doesn't. Go ahead and drop the spring arm off if you need to clean it up, rather than trying to do it on the car. I'm still going to have the alignment redone once the car is back together just for peace of mind. I'll update this forum with the results.

As I go through this process I've been collecting what appears to me to be sufficient evidence to write a scathing review of Tom Masano Mercedes of Reading, PA (USA), which I will do under separate cover. In the meantime here are my lovely, unobtanium spring arms. The steel is quite thick so I am not worried about these failing; I was going to replace them just to save the mess and effort of cleaning them. It was a bear.

 

Thanks for sharing , I'm sure this would help for DIYers as well

 

This idea may be the best one yet. I’ve watched a lot of videos and read the shop manual instructions and they all make it seem so easy to extract the air springs. I’ve seen one video where the mechanic (Harris Automotive) dropped the outer side of the spring control arm. Of course I can’t find the video again. But I had the thought and I’ve ordered a portable electric jackhammer because I just had a 4 wheel alignment as well. My control arms look just like yours so I also bought a wire wheel to clean it up and I will put some anti-seize grease on it.

 

Great tip!

I also replaced my air shocks on my s212 about 6 month ago and mine were also stuck in the control arms because of rust. Every youtube video showed a few taps with a normal hammer and the springs would just pop out. Mine were so stuck that I mangled that plastic underside and I had no tool to push them out. I had to cut the top half of the air-bag off and hack and saw and grind en dremel the rest of the underside out in pieces. It took me about 3-4 hours per side. ****tiest job I have ever done on a car. I then sanded away the rust from the air spring seats and painted it.

After that I couldn't get the new ones in because I could not get the control arm pushed down far enough so I destroyed the new set of springs, great... Then I ordered another set and I took out the shock dampeners and that gave me enough room and play to put the new ones in correctly.

So, if you're alone and you can't get the new springs in, remove the shocks. Fairly easy and it gives you a lot more room.

 

Great tip. I used a floor jack and a large socket and lifted up on the bellows

 

I tried using a socket on a jack on one of my many attempts to extract the air struts but it didn’t work for me. I’m convinced the gear puller is the best method.

 

I absolutely can relate to your pain. I’ve done this job 3 times on the driver’s rear because it wouldn’t seat properly. I destroyed my original bags while in the troubleshooting phase only to find out that the problem was the valve unit/block.🙄 However, if you use a scissor jack (and a block, if needed) between the rotor assembly and the wheel well, you won’t need to remove the shock. Just a tip.

 

After doing this job 2 times prior, because the bag wouldn’t seat properly, I decided to drop the control arm but couldn’t get the bolt out of the side closest to the center. I was also concerned about the alignment I just got. It was a bear to get the outer bolts back in.

 

I was so impressed with the gear puller idea that I ended up returning the jack hammer and purchasing a set of 3 gear pullers from Harbor Freight for ~$25. It worked so well that I’m convinced it is the best method to extract the rear air struts.

6 inch 3-jaw gear puller