HOW-TO: Replacing E500E SLS Rear Hydraulic Struts

[gerryvz]

Those blue crabs sound great standing off the back of the swim platform with a cold gin and tonic this evening!

Chesapeake Seafoods in Edgewater has awesome crabs. And my house is only literally a 3-minute drive from Cantler's, if you know that place. People come from all of the surrounding states to go to Cantler's, lol!

Cantlers

cantlers.com

 

[owenj99]

Very nice! We have a few smaller seafood places near me, and some on Kent Island as well. We normally get a dozen almost every weekend and head out on the water! My stepmoms family owns Mr. B's seafood market on Kent Island so we know most of the local crab businesses well as we supply crabs to a good bit of them! If you ever want some giant crabs just tell them Owen sent you!

 

[gerryvz]

CONFIRMING that one of the two rubber bushings is NLA from MB as a separate item. It appears that it may be still available as part of a "kit" containing the two needed rubber bushings for each side. I would consider buying at least two kits and replacing these bushings if you have never done this, or at least having two kits as spares for the time when you will need to replace your rear SLS struts.

 

[Matt-R20]

CONFIRMING that one of the two rubber bushings is NLA from MB as a separate item. It appears that it may be still available as part of a "kit" containing the four needed rubber bushings. I would consider buying at least one kit and replacing these bushings if you have never done this, or at least having a kit as a spare for the time when you will need to replace your rear SLS struts.

View attachment 142489

Is there a part number for the kit?

 

[Jlaa]

Is there a part number for the kit?

The part number is mentioned in the above postings, as well as below:

 

[gerryvz]

Is there a part number for the kit?

First post, listed under OPTIONAL in the parts list.

 

[Matt-R20]

The part number is mentioned in the above postings, as well as below:

View attachment 142515

First post, listed under OPTIONAL in the parts list.

Sorry fellas didn’t realize it was up there, will scroll next time. Thanks!

 

[gerryvz]

Sorry fellas didn’t realize it was up there, will scroll next time. Thanks!

No problem at all. We strive to be as complete as possible on the HOW-TOs as to relevant part numbers, difficulty, time required, tools required, and so forth.

If you're planning to do this job yourself, it's not that difficult and will solve your issue. I recommend that you also order a pair of Corteco spheres (mounted in the trunk spare tire compartment) and replace them at the same time while you have the rear hydro-legs out and the SLS system de-pressurized. Both of these part replacements are pretty much a once-in-an-ownership type of deal, and the spheres are pretty cheap at around $100 each.

 

[Matt-R20]

No problem at all. We strive to be as complete as possible on the HOW-TOs as to relevant part numbers, difficulty, time required, tools required, and so forth.

If you're planning to do this job yourself, it's not that difficult and will solve your issue. I recommend that you also order a pair of Corteco spheres (mounted in the trunk spare tire compartment) and replace them at the same time while you have the rear hydro-legs out and the SLS system de-pressurized. Both of these part replacements are pretty much a once-in-an-ownership type of deal, and the spheres are pretty cheap at around $100 each.

Thanks Gerry, agree the write ups you guys do are amazing. Any comment on the potential leak? Are there any weak points in the lines that are common? I’m assuming there are lines from the rear to the front to the pump?

 

[gerryvz]

You need to determine whether the leak is from the power steering part of the tandem pump, or the SLS portion. Both are contained in a single pump, with separate lines feeding and exiting each part of the pump. Typically the SLS part doesn't leak. The power steering most often leaks from the "short hose" part from the fluid reservoir to the pump itself. Somewhat less common is the "S" hose.

If you search for "short hose" and "S hose" you'll find plenty here about them, and HOW-TOs on replacing them. More description and photos of the underside of the car will help the experts here diagnose where the fluid is coming from.

 

[Matt-R20]

You need to determine whether the leak is from the power steering part of the tandem pump, or the SLS portion. Both are contained in a single pump, with separate lines feeding and exiting each part of the pump. Typically the SLS part doesn't leak. The power steering most often leaks from the "short hose" part from the fluid reservoir to the pump itself. Somewhat less common is the "S" hose.

If you search for "short hose" and "S hose" you'll find plenty here about them, and HOW-TOs on replacing them. More description and photos of the underside of the car will help the experts here diagnose where the fluid is coming from.

Awesome, thanks that helps me know what to look for. I didn’t realize the two systems were connected, lots to learn about how these cars work. And yes I’ll get the car in the air to get some photos and see what’s going on.

 

[gsxr]

SLS leaks are often from the front seal of the tandem pump, as the front portion of the pump is for SLS. The SLS system rarely leaks anywhere else.

The rear portion of the tandem pump is for power steering, and the P/S leaks are almost always hoses. The short hose between reservoir and pump is the most common, followed by the S-hose, then the straight hose along the frame rail. The steering box itself generally leaks from the output shaft at the Pitman arm. There are detailed writeups on the forum for all of these, I believe.

 

[mbzgurl]

Having driven the car on a 10-mile "shakedown" cruise after replacing the hydro-legs, and now about 70 miles on a day's commute to downtown Houston, all I can say is "WOW!!" what a difference. The rear of the car is quiet and just very poised. Well worth the cost, time and effort to replace them.

If you have the dreaded rear suspension clunk caused by worn bushings in the rear hydro-struts, you won't be disappointed by this repair. It's more or less on par with the motor+transmission mount for overall satisfaction and bringing that "smooth, stock" quality back to your ride.

Cheers,
Gerry

Exactly what my car needs! All of it...plus the motor+transmission mounts, and sooooo what is all this going to cost me?

 

[gsxr]

Exactly what my car needs! All of it...plus the motor+transmission mounts, and sooooo what is all this going to cost me?

Depends if you can DIY the work, or at the mercy of the local indy shop. If it's the latter, do you know their labor rate per hour?

 

[nocfn]

I think the e500 has a lot of room to work on it and under it with ramps. Proper jacks/chocks/stands and you are good to change out engine mounts. Proper tools is a must, cannot just wing it.

 

[gerryvz]

Depending on parts and labor prices, count on a $1,200-1,500 bill, particularly if they charge you MB list price (I think it was most recently $570 each?) for the struts. I don't know what the labor spec is for the job, but I can't believe it would be less than 3-4 hours. At $125 an hour, do the math.

 

[mbzgurl]

Depends if you can DIY the work, or at the mercy of the local indy shop. If it's the latter, do you know their labor rate per hour?

I have a mechanic who charges less than the Mercedes shop he works for during the week. He comes to my house after work when I need him, luckily I haven't needed any major work done so far and he hasn't billed me. I can't wait to get the rears done! He diagnosed the hydraulic system a few weeks ago for his own curiosity. It's been disconnected since I bought the car. All it needs are the leaky lines near the rear wheels replaced. I need to source those cuz the dealer doesn't have them. I will gladly pay him to help me get this job done. He'll be happy we're finally going to fix er' up and get rid of that speed bump clunk.

Yesterday I drove through a construction zone and popped a tire. The tow truck guy had a hard time getting the car on the flatbed cuz it was so low the tailpipe was scraping the ground. Well, the right rear bumper bracket broke. Where can I get that part and does it need to be riveted to the inside of the bumper? Hopefully, the tow company will compensate me.

 

[gsxr]

...All it needs are the leaky lines near the rear wheels replaced. I need to source those cuz the dealer doesn't have them. I will gladly pay him to help me get this job done. He'll be happy we're finally going to fix er' up and get rid of that speed bump clunk.

The lines near the rear wheel should be available new at the dealer, but are likely special order from Germany. It's a formed pipe + hose assembly.

Passenger side is 124-997-70-82
Driver side is 124-997-71-82 up to chassis B808054
Driver side is 124-997-72-82 as of chassis B808055 (possibly NLA, not sure what is different vs the earlier #71)

These are ~$150/ea list, ~$125 from discount dealers. EPC screenshot below.

 

[mbzgurl]

The lines near the rear wheel should be available new at the dealer, but are likely special order from Germany. It's a formed pipe + hose assembly.

Passenger side is 124-997-70-82
Driver side is 124-997-71-82 up to chassis B808054
Driver side is 124-997-72-82 as of chassis B808055 (possibly NLA, not sure what is different vs the earlier #71)

These are ~$150/ea list, ~$125 from discount dealers. EPC screenshot below.

View attachment 142865

Thanks for posting the diagram! I will send it to my mechanic who can show me what I need to order. Didn't think they were going to cost that much. Oh well....

 

[gsxr]

Those are the lines which connect to the SLS shock - I was assuming that is what you were referring to. There are other hard lines from the junction block to the valve and nitrogen spheres (callouts #'s 63, 67, 69 in the diagram). It would be unusual to have a leak from those, and might require cutting & bending a piece of bulk metric tubing to replace if any are damaged. Definitely need the mechanic to confirm which items are bad before ordering.

 

[Jlaa]

The lines near the rear wheel should be available new at the dealer, but are likely special order from Germany. It's a formed pipe + hose assembly.

Passenger side is 124-997-70-82
Driver side is 124-997-71-82 up to chassis B808054
Driver side is 124-997-72-82 as of chassis B808055 (possibly NLA, not sure what is different vs the earlier #71)

These are ~$150/ea list, ~$125 from discount dealers. EPC screenshot below.

View attachment 142865

I just recently purchased 124-997-72-82 in Q4/2021. It was shipped from DE to Naperville, IL, and then to me.

 

[gerryvz]

CONFIRMING that one of the two rubber bushings is NLA from MB as a separate item. It appears that it may be still available as part of a "kit" containing the two needed rubber bushings for each side. I would consider buying at least two kits and replacing these bushings if you have never done this, or at least having two kits as spares for the time when you will need to replace your rear SLS struts.

View attachment 142489

Is there a part number for the kit?

The part number is mentioned in the above postings, as well as below:

View attachment 142515

The kits are very definitely still available from MB, but the bushings are NLA individually.

Each SLS kit (two are required) contains a set of two bushings -- enough to do one SLS hydro-leg.

Here are some photographs of the kit, as it ships today from MB. You can see from the 10-2021 production date, that this is recent schizz.

MB part number 124 320 03 56.

 

[Matt-R20]

The kits are very definitely still available from MB, but the bushings are NLA individually.

Each SLS kit (two are required) contains a set of two bushings -- enough to do one SLS hydro-leg.

Here are some photographs of the kit, as it ships today from MB. You can see from the 10-2021 production date, that this is recent schizz.

MB part number 124 320 03 56.
View attachment 143243 View attachment 143244 View attachment 143245 View attachment 143246 View attachment 143247

Thank Gerry, as usual very comprehensive and helpful. I reread the full post and am slightly confused. The clunk described is attributed to the lower busing, I’m assuming where it meets the control arm. Does a new hyrdro strut not come with bushings installed and therefore one needs a bushing set? Or will a new strut have this hardware? Maybe to say a different way, if the bushing is the cause of the clunk I’m assuming you could replace just the bushing to solve that? You wouldn’t have a fresh suspension, but you’d be rid of the clunking noise? Thanks for all your help!

 

[gsxr]

The lower bushing is part of the SLS hydroleg and not replaceable separately (at least, not with OEM components).

The upper bushings, washers, and nuts are not included with the hydroleg and must be purchased separately as a hardware kit.

Clunking noises are generally EITHER from the lower bushing (spherical joint, not a rubber bushing) with significant wear/play, OR from internal failure of the hydroleg. This also assumes the hydraulic system is filled and properly bled - there may be noises if the system is not filled/bled correctly.

 

[Matt-R20]

The lower bushing is part of the SLS hydroleg and not replaceable separately (at least, not with OEM components).

The upper bushings, washers, and nuts are not included with the hydroleg and must be purchased separately as a hardware kit.

Clunking noises are generally EITHER from the lower bushing (spherical joint, not a rubber bushing) with significant wear/play, OR from internal failure of the hydroleg. This also assumes the hydraulic system is filled and properly bled - there may be noises if the system is not filled/bled correctly.

Thanks makes sense!

 

[gerryvz]

As said, the clunking noise is about 90% of the time, from the lower bushing on the bottom of the SLS hydro-leg. The photos of my bushing from the HOW-TO should show the conditions where it is degraded as compared to a new one.

 

[Matt-R20]

As said, the clunking noise is about 90% of the time, from the lower bushing on the bottom of the SLS hydro-leg. The photos of my bushing from the HOW-TO should show the conditions where it is degraded as compared to a new one.

View attachment 143307

I was confused about lower bushing in the kit, but now understand its the upper bottom bushing vs lower bushing on the strut itself. Rookie learning….

 

[gerryvz]

Yes, the two round rubber bushings isolate the top of the hydro-leg from the car’s body. I think I illustrated replacement of these two bushings in the HOW-TO, but my memory may be off as it was some years ago now.

 

[maw1124]

As said, the clunking noise is about 90% of the time, from the lower bushing on the bottom of the SLS hydro-leg. The photos of my bushing from the HOW-TO should show the conditions where it is degraded as compared to a new one.

View attachment 143307

When I went through this I could never get anyone to spot any play in the bushing. So I just sprang for hydrolegs. People thought I was burning cash because they looked fine too -- no seepage no play no nothing. They condemned the RENNtech heim joints. Of course it was both the hydro legs AND the heim joints.

So, when faced with replacing a bushing in a hydro leg or replacing the hydro leg itself with bushing included, I sort of couldn't convince myself I wanted a new bushing in a 20 year old hydroleg. My brain wouldn't accept that as an answer. I suppose YMMV.

maw

EDIT... "grim joints" LOL... I also got rid of the heim joints and reverted to stock links. Had to do something extra for camber on the lowered stance ("RENNtech Rear Subframe Mod" they called it back then) but @gsxr helped me through that.

 

[whitehawk]

Do these used hydro legs have any value? Does anyone press in new bushings? I really don’t like throwing away parts.

 

[gsxr]

Check if the foam buffers are intact... if so, and not leaking, they should be worth something!

IME the spherical joint (aka "bushing") is not a common failure. I've never encountered one personally.

 

[sheward]

Hang on to them. I still have my old ones and others do too. One day I intend to retro fit a new bushing. They may not be so easy to replace in the future.

 

[jnes]

What is the cheapest place to source new hydrostruts at the moment? Local dealer want's 1240€ for the strut..

 

[TerryA]

What is the cheapest place to source new hydrostruts at the moment? Local dealer wants 1240€ for the strut..

Naperville mboeparts.com has them listed at $326.00 apiece. One other online dealer had $325.00 on them. Another said NLA

 

[gsxr]

Naperville is $399, MSRP is $540 each, for hydroleg 124-320-42-13:

https://www.mboemparts.com/oem-parts/mercedes-benz-hydropneumatic-spring-leg-1243204213

@jnes, try contacting the MB Classic Center in Irvine, CA. They may sell them around $400 USD each plus international shipping. Not many USA vendors will ship internationally.

https://partssearch.mercedes-benz-classic.com/parts/A1243204213

Alternately, you can get the OEM Sachs (#102-503) for ~$800 USD including delivery to Europe:

Mercedes Shock Absorber - Sachs 102-503

Mercedes Shock Absorber - Sachs 102-503

www.fcpeuro.com

Edit: As of late 2023, MBCC is showing NLA for the rear SLS shocks:

 

[TerryA]

@gsxr, Dave I came up with 1243203413 @MBoemparts.com by listing year, model & rear suspension. It said 500E500 self leveling $326.00 I just checked again now it says $322.00.

I see you used a different part# 1243204213 and came up w/$399.00

Are they listing a standard rear shock for the 500E500?

What gives?

 

[gsxr]

@gsxr, Dave I came up with 1243203413 @MBoemparts.com by listing year, model & rear suspension. It said 500E500 self leveling $326.00 I just checked again now it says $322.00.

I see you used a different part# 1243204213 and came up w/$399.00

Are they listing a standard rear shock for the 500E500? What gives?

Terry, you made the mistake of trusting an internet part catalog! These are riddled with errors. Naperville's isn't any better. All the online dealers share the same Revolution Parts platform and catalog/fitment info, the only difference between dealers is pricing (and, some will show NLA / Discontinued sooner than others).

In this case, p/n 1243203413 was the old part number which included the SLS shock *and* also the hardware kit. This was replaced / superceded to p/n 1243204213 which is the SLS shock only, without hardware. You have to buy hardware kit 1243200356 separately (qty 2, one per shock).

If you order 1243203413 you will receive, and be charged for, 1243204213.

EPC screenshot below. Remember to ALWAYS use the EPC to look up part numbers. NEVER use the internet catalogs.

 

[jnes]

Great. I have purchased those mounting kits separately..

@jnes, try contacting the MB Classic Center in Irvine, CA. They may sell them around $400 USD each plus international shipping. Not many USA vendors will ship internationally.

Thanks for the tip! By the way does Tom Hanson still work with MB CC at Irwine CA? I have ordered him from the past..

 

[jnes]

Okay, contacted to MB Classic Center and they are not able to ship items overseas due to that shocks are considered as hazardous material..

Never heard that before..

 

[gsxr]

Okay, contacted to MB Classic Center and they are not able to ship items overseas due to that shocks are considered as hazardous material..

Never heard that before..

They are probably thinking of standard shocks, which have hydraulic fluid inside, which could be considered hazardous.

The SLS rear shocks are non-pressurized and have no fluid inside. They can ship them overseas, if you can find a person there who understands this.

 

[jnes]

They are probably thinking of standard shocks, which have hydraulic fluid inside, which could be considered hazardous.

The SLS rear shocks are non-pressurized and have no fluid inside. They can ship them overseas, if you can find a person there who understands this.

I asked that but got no response atm.. Also replying to the mails is a bit odd. They use caps, no sentences etc..

Anyway does anybody have direct contact to Classic Center rather than general part inquiry address?

Or any volunteers to help me to get shocks?

 

[jnes]

Ok, find out that Autohausaz is willing to ship overseas and their price seems good, 379,99 $. I guess that it is ok place to order parts. Is there any discount codes available which should be aware before purchasing order?

 

[gsxr]

Ok, find out that Autohausaz is willing to ship overseas and their price seems good, 379,99 $. I guess that it is ok place to order parts. Is there any discount codes available which should be aware before purchasing order?

I don't know if any discount codes, but I'd email them and ask about pricing & availability before placing an order. I am only seeing the old part number on their site, and that number likely won't be available when they try to get them...

https://www.autohausaz.com/pn/MB-1243203413

 

[Trae]

Great. I have purchased those mounting kits separately..

Thanks for the tip! By the way does Tom Hanson still work with MB CC at Irwine CA? I have ordered him from the past..

No, Tom retired last year.

 

[gerryvz]

Is there a guide already for the spheres too?

For reference of others who may need this information in the future, we do now have a guide to replacing the hydropneumatic rear SLS spheres.

You can find this at the following link:

HOW-TO: Replacing W124 Rear SLS (Self-Leveling Suspension) Spheres | "HOW-TO" Tutorial Articles

Starting around the May 2022 time frame (and possibly before), I noticed on several long-distance trips up to the NYC area, that the damping and bump-absorption capability of my E500's rear suspension was severely diminished. It was basically not absorbing bumps, and every time I would drive...

www.500eboard.co