Reinstalling W126 self-leveling rear suspension

The previous owner of my 560SEL had the self-leveling rear suspension removed.    He told me that he was having problems with it, and the suspension shop he took that car to (Pedders) advised him to remove it.   This was pretty bad advice, but he wasn’t to know that.   A 560SEL should have a supple ride, but my car rode like an old pickup truck.   The Pedders springs and shocks were overly firm and caused the rear to bounce around.   It may have been better with three heavy adults in the back but my children are six, four and four, so even with them in the car, the ride was no better.

Obviously a W126 can ride well without self-leveling suspension.   It was only standard on the 560 models and all models sold in Australia.    The models originally not equipped with self-leveling suspension had specific springs and spring pads to ensure a good ride.   In the workshop manual there is a rather complex table where you work out the number of points you car has based on the model and installed options and that determines the springs and spring pads that should be used.

Instead of reinstalling W126 self-leveling rear suspension, I could have procured the right springs for my car.   560SELs were never sold without SLS, but 500SELs were, so I could have extrapolated the number of points and used springs for a heavily optioned 500SEL.   The cost of this approach probably wouldn’t have been a great deal less than putting back in the correct suspension for my car.

The main reasons why I decided reinstalling W126 self-leveling rear suspension was the best approach was that I really like the way this suspension rides; It is the correct suspension for my car; and the system had been removed in a way that made reinstallation reasonably straightforward.   In a previous article I went over this and the parts I would need.  If the pump had been removed and blanked off, and leveling valve removed, this would have made things much harder.

I found a set of good used struts and springs from a local Mercedes dismantler.   They were not cheap.   I am still on the look out for another spare set.   At the time, I considered having them rebuilt but they were not leaking and seemed in good condition.

I had the work done about a year ago.   At the time I was quite busy with work and forgot to write up the article.   I also hadn’t been back under the car to take some photos.   I didn’t attempt this myself as I wasn’t comfortable compressing the springs, and reinstalling W126 self-leveling rear suspension is quite different from just simple component replacement.    Down the line, If I have a bad accumulator or leaking strut, I would probably do this myself.

The photo above shows the re-installed strut and spring combination.    The spheres and hoses are all new parts, as are the rubber bushings.   I also needed a new control rod to set the height.   Used accumulator sphere are available, but I would advise against them. They are a wear item.

After the system was installed, I took the car for a long drive.   What a difference.   It really is transformed.   It now drives like an S-Class should.   Even thought it ended up being expensive, I do not regret reinstalling W126 self-leveling rear suspension.   The main advice I would give anyone who has one of these cars is not to remove it.   Most of the time it is removed at significant expense, the issue can be traced back to worn out accumulator spheres.   They are not that expensive and easy to replace.   The struts can be rebuilt, pumps re-sealed, hoses repaired and so on.   I’ve now driven the car another 5,000km, and I really enjoy the ride in this car.

I’m still on the hunt for another set of struts.  I recently found a set for a very good price in the USA, but Fedex lost my package.  It also contained some workshop manuals I had been searching for a long time as well.