W124 E320 Wagon rear shock conversion
 

Hi all, just picked up my new to me 1994 E320 wagon last night and I’m ready to commence the rehabilitation of another fine German car. (I like the sound of rehabilitation better than repair) I just love the room in the wagon but just hope my brain will adapt to the automatic transmission soon. I feel so silly pushing on the floorboard with my left leg as I reach for the gear selector. =)

After reading through the posts, I have not seen any rear suspension conversions on W124 wagons to conventional rear shocks. Has this been done or at least investigated?

I realize that many wagon owners may enjoy the system and I can certainly appreciate that. I’m sure it’s a great system and do not want anyone to get the idea that I’m advocating otherwise.

I will post my trials and tribulations in case anyone else should ever want to look into converting their W124 wagons. Additionally I welcome all assistance/input form those who are willing.

I hope to locate a sedan locally or enlist the services of someone on the forum who has access to one so that I can get some pictures and measurements.

From initial observations of a few pictures I found on the web of the self-leveling and the conventional sedan shocks, I know that both top and bottom mountings are different.

To mount the bottom, it looks like I will need to either change out the trailing arms (and more as needed) or fabricate a bracket. Initially I feel going with the bracket may prove to be a simpler solution so that’s where I will begin. I’ll take some measurements and pictures this weekend and see what ideas come to surface on bracket possibilities.

For the top mount, I will need to look at a sedan/coupe or cab to see how the mounting differs.

If anyone has a sedan/coupe or cab and you live in or near the Columbia SC area and would be willing to let me take a peak at your rear damper area, please let me know!

This weekend I’ll be giving my newly acquired E320 wagon (aka the Queen Family Truckster) a full detail and will not be back in front of a PC again until Monday.

Thanks and have a great weekend!
Steve
Columbia, SC

Are You sure that you need to swap out all the items?

As I Did My W210 Estate and changed out the Power steering pump to a sedan one and replaced the self level struts with Normal Shocks...No Other Work Required...

The hydraulic struts partially support the weight of the car in addition to supplying damping. You would need to replace the springs with substantially higher rate springs to do the job right. Otherwise the tail end of the wagon will ride low, handling and tire life will be compromised, and of course that 1150lb load rating is gone. I've never heard of an aftermarket set of springs for the wagon.

The self leveling system provides a nice compromise between ride, handling, and load rating. It's probably also cheaper to repair it than replace it.

- JimY

Steve, we also just got a wagon (the Windstar is GONE:D ). Opinion of other owners on web is that mostly the spheres go bad (lose gas charge internally) then the ride gets bouncy (compressed gas is the shock absorbing medium). The struts are usually not bad. I would not swap to a conventional system. I can confirm that the springs are different capacity (H&R lowering springs are different for conventional and hydro-pneumatic systems) as Jimy stated.

Replacement of the Mercedes self-leveling system is not feasible.

It's not a Volvo (it's not Boge Nivomats).

Well, got under the rear end this weekend and removed the plastic trailing arm cover. It looks like the std rear shock may be able to bolt in without a bracket at all. Or at most, drill a new hole between the 2 existing holes to keep the conventional shosk centered.

Yes Jimy, I was also thinking about the fact that the self-levelers assist the springs in holding the car up and that the stock springs would certainly be too soft. Seems the accumulators (spheres) are actually the dampers in the system.

Man I totally forgot about the steering, thanks Mark Cummins!

KENT,
Do you have any more detail on the swap NOT being feasable?

I feel that the shocks physically mounting or to get them to fit are feasable. I hope that sourcing some stiffer springs will prove feasable. Plugging the shock lines or replacing the pump seems feasable enough. Am I to hit a wall here soon in this plan with something that I have not thought of yet but that you know of?

Any input is appreciated!

Thanks!

Steve Hauptmann
Columbia, SC

According to the local M.B. dealer and most tech guys I know the switching of the rear self levelling suspension to the standard set fitted to the sedan is IMPOSSIBLE!*

The dealer's shop manager and the some good independent techs have explained to me in detail how the switch will not work. The problem is that they did many years ago and I vaguely remember the exact technical reasons.

Basically:

-> MOST suspension components from the sedan and the wagon are different due to the lower wheel well height fitted to the wagon to provide a bigger cargo area.

-> The shock absorbers are completely different in terms of height, diameter, fixing points and travel.

-> Cutting off the hydraulic lines is not that simple, it will involve messing with the power steering among other things.

-> As far as I understand, the scenario is this: switching from self levelling to standard on a W124 sedan is possible with some expensive parts (the sedan could be optionally fitted with the rear self levelling suspension on most world markets at extra cost). In case of the wagon: simply just not possible.

-> To completely redesign your rear suspension setup with new parts, springs and absorbers would be far more expensive than to pay for spheres, schocks and hydraulic oil motors for the rest of your wagon's life.

* (In terms of cost and engineering feasibility).

I just changed the accumulators in my 95 320E wagon. Wasn't that bad a job and cost me about $200 in parts. I do have a lift in my shop that made the task go easier than doing it on jackstands.
I can't see how replacing the SLS could be cheaper or less work, or give a satisfactory result.

Thanks to everyone for all the information/input. I'm a little depressed now though as I thought it would be possible.

I really like the idea of reducing complexity and future repairs and was looking foward to bilstiens all the way around.

Sounds like to get rid of my bouncy rear end on the 94 e320 wagon, I just need to replace the accumulators and forget about the conversion.

Thanks again to all who posted!

Steve
Columbia, SC

When you get the current system up to spec again--anything requires periodic maintenance--you'll enjoy the benefits of self-leveling, which is something any conversion won't offer. Nothing depressing about that.

If you're anxious to "convert" something, why not look into different rear hydraulic struts and perhaps associated components as specified for Sportline or AMG models?

Steve

Flushing the system fluid and making sure the screen/filter is clean definitely helped improve the rear ride of the 95 wagon.

Do yourself a favor and replace the front and rear sway bar bushings. Cheap and easy to do. Don't use any petroleum products on the rubber bushings, just light application silicone spray. Check the quality of the rear sway bar link connector ends. They are inexpensive and often start to subtly fail.

Haasman

Hi to every one! I m new here and i need some help about the rear shock conversion.

I purchace a kit of air shock from:

SLSCONVERSION.COMAnd i want to know if someone have buy one of those kit! It is not working on my car !!! And it look exactly the same as on is website. The problem seem to be that the shock it self is about 3 to 4 inchs to long, first:
The piston is all the way in the shock and the car sit on it. Second: If putting air in it, about 120 psi. the car is raising, well ok but the piston is still full inside, only the ballon in the shock is raising the car, so there is no absorbing effect on the car, just ride like with to basket ball ballon under the car! So i figure that they are 3-4 inchs to long ! I can not run the car at all cause its to bouncy and dangerous. I paid about 275$ for this kit, including the shipping. Somebody can help me for this problem, cause it look like i m the onlyone to have purchace a kit like this and i cant not find no more is link on E-bay ! Thank you in advance, Maxime

Didn't you read the posts regarding converting a w124 rear suspension?

You wasted your money on the conversion. Buy the correct accumulators from PeachParts, install them and enjoy a great suspension in the wagon.

Nope, not here
 

Maxum, I've followed this forum for at least 10 years, and had to fix SLS on my TE (worn accumulators, one leaking strut, bad tandem pump). I'm certain no one here has posted about installing the air system you bought, or at benzworld dot org. Maybe you can search over at mbworld dot org, but I think you should have searched and read up about 124 chassis SLS before you bought the air mess.

Live and learn.

Am glad you caught yourself before attempting. when I get under my wagon I sometimes just stare and wonder in amazement, kind of "what in the world were they thinking?" To me it's almost as if the designers and the engineers had a fight and the designers won. So the engineers came up with a "I told you so" system.... the only other time i felt that was was looking at the cooling system on my 93 Eurovan. At least the SLS on the wagon works.