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I recently purchased the aforementioned ML550 with 92K miles on the clock from Bring a Trailer. When I first drove it, I was expecting a solid ride. What I got was anything but that. Driving over uneven pavement set off pre-collision error warnings, and making any sort of turn felt almost like I was driving on ice. I have used Claude for doing some diagnosis, and it has been pretty good at making recommendations, but I would really love some input from the community here who drive these vehicles every day.
Unrelated to the suspension, I have had to deal with some other pressing technical issues, and have thus far replaced:
Spark Plugs x8 Bosch ZR6SII3320 Double Iridium — Pack of 10 (2 spares)
Spark Plug Lubricant Permatex 22058 Dielectric Grease 3oz — replaces MB lube
Coil Boots x8 TRQ 8-Piece Set
(I have a borescope camera, and I do have some REALLY minor scoring in 4 of the 8 cylinders, but you can still see the cross-hatching through it)
Turbo Coolant Line Left REIN 2782000400
Turbo Coolant Line Right REIN 2782000800
Turbo Coolant Line Left REIN 2782000900
Upper Radiator Hose Genuine Mercedes — M278 Engine Specific
Lower Radiator Hose REIN CHR0965 — Confirmed Fitment
Expansion Tank/Reservoir REIN EPK0126 — With OE Cap and Fluid Level Sensor
Expansion Tank Upper Hose REIN CHE0960 — Expansion Tank to Radiator
Expansion Tank Lower Hose REIN CHE0955 — w/o Heated Windscreen Washer
Heater Hose Genuine Mercedes
Coolant Breather Pipe OEM 1665001091 — Expansion Tank to Radiator
REIN Water Hose Expansion Tank to Aux Water Pump — w/o Heated Washer
Thermostat Assembly Wahler — Confirmed Fitment 2014 ML550
Water Pump HEPU — Metal Impeller, OEM Supplier
Water Pump Gasket Mahle/Clevite C33423 — Molded Rubber
Belt Tensioner Gates GA-2782000570
Center Idler Pulley INA 6112340293
Right Upper Idler Pulley Febi 2782020519
Left Idler Pulley Febi 2782020619
Lower Idler Pulley Febi 2782020219
Serpentine Belt Continental 6PK2528 — Confirmed via Mercedes VIN lookup
(I also flushed the coolant system after everything was replaced using G48 coolant)
Transmission Filter Kit Febi Bilstein — Filter, Pan Gasket, 6 Bolts, Overflow Pipe, Drain Plug, Drain Plug Seal
ATF Fluid x2 5L jugs Fuchs Titan ATF 7134 FE — Explicit MB 236.15 Approval — First Service
For the rear end, I replaced
Rear Sway Bar Links-- Lemforder 1643201232 — OEM, 2 per vehicle
Rear Shock Absorber — Pair AISIN SAKMB-01365 — Confirmed Fitment, Excludes ADS — Set of 2
I have not replaced any bushings on the rear and I haven't done the springs because I am not 100% sure they need it, but am prepared to do so.
For the front, I am going to be replacing
Front Strut Assembly — Pair AISIN SAKMB-01366 — Fully Loaded, Includes Spring/Mount/Boot/Bump Stop — Set of 2 Mercedes Control Arm Bushing Kit - Lemforder (FCP Euro) including:
1 Suspension Control Arm Bushing LEM-3970101
1 Suspension Control Arm Bushing LEM-3970201
2 Suspension Control Arm Bushing MER-1663330100
2 Suspension Control Arm Bushing FEB-47994
1 Suspension Stabilizer Bar Link LEM-3713501
1 Suspension Stabilizer Bar Link LEM-3713601
Now, where I am looking for advice and guidance is this-- What else? I am pretty technically proficient, and I am doing this maintenance myself, thanks to YouTube and various other sources. I have a FoxCon scanner with Mercedes software, but when it comes to the ride quality, I am out of my depth aside from throwing parts at it. I do expect that once I have the front end components installed, the ride quality and stability will be magnitudes of order better, but if it's still not behaving like a Mercedes should, I am not entirely sure what would be next. I was really surprised to see how bad the rear struts were. the bump stops were pretty beat up along the bottom, so those shocks have been gone for quite some time. I expect the front to be just as bad.
What that PROBABLY means is that since the shocks/struts weren't doing their job, the rest of the system took WAY more abuse than it should have, and there are other components that are failed or about to fail. My rear springs have a light blue and a green marking on them, and I have no idea what that means in terms of replacement. The green is the same color as Mercedes uses to mark parts from the factory, so that may just be that, but I have no idea, and the internet hasn't been conclusive. I will include a couple of images of the springs and their condition to see if that adds anything to the conversation. This shows some curvature to the spring, which I don't know if that's normal or a sign that they are failed/failing.
The barcode on here just reads 5 9240, which doesn't translate to anything I can find.
So, with that, any advice/counsel that the community can provide is very much appreciated. My plan at this point is to get the front end parts replaced and see where things stand, because when so many things are broken, it's really hard to narrow a focus down, but if anyone on here has been through this, and they ultimately got things dialed in, I really appreciate the help.
You understand well how fresh parts are necessary to restore lost performance.
You have replaced a good deal of parts, the bad ones are those awaiting.
MB suspensions are designed with interactive links torquing on each other through soft bushings.... everything must go!
MB uses soft-steel spring coils that age to become short out of spec.
As we know, suspensions benefit from adjustable arms and/or corrective camber bolts.
Hope this helps you restore straight tracking.
Last edited by CaliBenzDriver; Apr 10, 2026 at 11:34 PM.
You understand well how fresh parts are necessary to restore lost performance.
You have replaced a good deal of parts, the bad ones are those awaiting.
MB suspensions are designed with interactive links torquing on each other through soft bushings.... everything must go!
MB uses soft-steel spring coils that age to become short out of spec.
As we know, suspensions benefit from adjustable arms and/or corrective camber bolts.
Hope this helps you restore straight tracking.
You are a genie!!! I am now working on the front upper and lower control arms. If you have any suggestions on how to access the rear driver's side nut, you will be my hero!!!
You are a genie!!! I am now working on the front upper and lower control arms. If you have any suggestions on how to access the rear driver's side nut, you will be my hero!!!
I recently purchased the aforementioned ML550 with 92K miles on the clock from Bring a Trailer. When I first drove it, I was expecting a solid ride. What I got was anything but that. Driving over uneven pavement set off pre-collision error warnings, and making any sort of turn felt almost like I was driving on ice. I have used Claude for doing some diagnosis, and it has been pretty good at making recommendations, but I would really love some input from the community here who drive these vehicles every day.
Unrelated to the suspension, I have had to deal with some other pressing technical issues, and have thus far replaced:
Spark Plugs x8 Bosch ZR6SII3320 Double Iridium — Pack of 10 (2 spares)
Spark Plug Lubricant Permatex 22058 Dielectric Grease 3oz — replaces MB lube
Coil Boots x8 TRQ 8-Piece Set
(I have a borescope camera, and I do have some REALLY minor scoring in 4 of the 8 cylinders, but you can still see the cross-hatching through it)
Turbo Coolant Line Left REIN 2782000400
Turbo Coolant Line Right REIN 2782000800
Turbo Coolant Line Left REIN 2782000900
Upper Radiator Hose Genuine Mercedes — M278 Engine Specific
Lower Radiator Hose REIN CHR0965 — Confirmed Fitment
Expansion Tank/Reservoir REIN EPK0126 — With OE Cap and Fluid Level Sensor
Expansion Tank Upper Hose REIN CHE0960 — Expansion Tank to Radiator
Expansion Tank Lower Hose REIN CHE0955 — w/o Heated Windscreen Washer
Heater Hose Genuine Mercedes
Coolant Breather Pipe OEM 1665001091 — Expansion Tank to Radiator
REIN Water Hose Expansion Tank to Aux Water Pump — w/o Heated Washer
Thermostat Assembly Wahler — Confirmed Fitment 2014 ML550
Water Pump HEPU — Metal Impeller, OEM Supplier
Water Pump Gasket Mahle/Clevite C33423 — Molded Rubber
Belt Tensioner Gates GA-2782000570
Center Idler Pulley INA 6112340293
Right Upper Idler Pulley Febi 2782020519
Left Idler Pulley Febi 2782020619
Lower Idler Pulley Febi 2782020219
Serpentine Belt Continental 6PK2528 — Confirmed via Mercedes VIN lookup
(I also flushed the coolant system after everything was replaced using G48 coolant)
Transmission Filter Kit Febi Bilstein — Filter, Pan Gasket, 6 Bolts, Overflow Pipe, Drain Plug, Drain Plug Seal
ATF Fluid x2 5L jugs Fuchs Titan ATF 7134 FE — Explicit MB 236.15 Approval — First Service
For the rear end, I replaced
Rear Sway Bar Links-- Lemforder 1643201232 — OEM, 2 per vehicle
Rear Shock Absorber — Pair AISIN SAKMB-01365 — Confirmed Fitment, Excludes ADS — Set of 2
I have not replaced any bushings on the rear and I haven't done the springs because I am not 100% sure they need it, but am prepared to do so.
For the front, I am going to be replacing
Front Strut Assembly — Pair AISIN SAKMB-01366 — Fully Loaded, Includes Spring/Mount/Boot/Bump Stop — Set of 2 Mercedes Control Arm Bushing Kit - Lemforder (FCP Euro) including:
1 Suspension Control Arm Bushing LEM-3970101
1 Suspension Control Arm Bushing LEM-3970201
2 Suspension Control Arm Bushing MER-1663330100
2 Suspension Control Arm Bushing FEB-47994
1 Suspension Stabilizer Bar Link LEM-3713501
1 Suspension Stabilizer Bar Link LEM-3713601
Now, where I am looking for advice and guidance is this-- What else? I am pretty technically proficient, and I am doing this maintenance myself, thanks to YouTube and various other sources. I have a FoxCon scanner with Mercedes software, but when it comes to the ride quality, I am out of my depth aside from throwing parts at it. I do expect that once I have the front end components installed, the ride quality and stability will be magnitudes of order better, but if it's still not behaving like a Mercedes should, I am not entirely sure what would be next. I was really surprised to see how bad the rear struts were. the bump stops were pretty beat up along the bottom, so those shocks have been gone for quite some time. I expect the front to be just as bad.
What that PROBABLY means is that since the shocks/struts weren't doing their job, the rest of the system took WAY more abuse than it should have, and there are other components that are failed or about to fail. My rear springs have a light blue and a green marking on them, and I have no idea what that means in terms of replacement. The green is the same color as Mercedes uses to mark parts from the factory, so that may just be that, but I have no idea, and the internet hasn't been conclusive. I will include a couple of images of the springs and their condition to see if that adds anything to the conversation. This shows some curvature to the spring, which I don't know if that's normal or a sign that they are failed/failing.
The barcode on here just reads 5 9240, which doesn't translate to anything I can find.
So, with that, any advice/counsel that the community can provide is very much appreciated. My plan at this point is to get the front end parts replaced and see where things stand, because when so many things are broken, it's really hard to narrow a focus down, but if anyone on here has been through this, and they ultimately got things dialed in, I really appreciate the help.
How much did all the suspension work cost in terms of parts and labor? And how much was all the other unrelated stuff?
This one is relatively straightforward to get off, but getting your hand down in there to thread it back on was... it took some creativity. And determination. And luck. You have to remove the airbox on the driver side to access it.
How much did all the suspension work cost in terms of parts and labor? And how much was all the other unrelated stuff?
I sourced my parts from FCP Euro, AZ Autohaus, and Rock Auto. I am into this for around $3K for parts, because I price shopped every component across the list. I only used OE parts, Lemforder for suspension, etc. The ONE non OE component I went with was the struts, opting for Aisin. The Aisin units came ready to bolt in, and I didn't have to try to salvage the mounts, bumpstops and the like. On top of that, all four corners were less expensive than the Sachs units for thw front, which are just the strut. I sourced them from CarParts.com.
Claude was actually really helpful through the process, helping me find part numbers, etc., much more quickly, and it actually built me a parts list and made suggestions on which parts to do together. I will go back and break it out later, because I am working on the rest of the front suspension.
All of the labor is me, and I have about 30 or so hours into it thus far. I'm probably 60% done.
To have a shop do this would easily run into 5 figures, because there is so much disassembly to getbto ANYTHING. I didn't even bother getting estimates because I'm unemployed right now, and I have more time than money. I consider myself on the higher end of DIYer, but there are tons of great videos on YouTube, aside from anything on these upper control arms.
Last edited by HuskEric; Apr 18, 2026 at 12:35 PM.
How much did all the suspension work cost in terms of parts and labor? And how much was all the other unrelated stuff?
We got a 2013 ML550 awith 65.000 miles and did well until 102.000; All of suddendly it started using a quart of oil every 500 miles.Paid a lot in diagnosing to include having mercedes do the oil change. I usually do my own oil changes and was careful in the amount so I felt for their money pit of maybe wrong oil and wrong amount. After several weeks, they removed my spark plugs and found scuffing on all cylinder walls. They said it was normal for over 100.000 but after doing a ton of research, Mercedes spray the inside of the cylinder wall from 2013 to mid 2015 engine and did not use iron insert to save weight. ( better gas milage to avoid the 16mph luxury tax for that did not meet EPA MPG). we replaced the engine with 2016 CLS with 91.000 and now have 140.000 and no issuess. Mercedes wanted 46.000 dollars to do it and my way was 16.000. There is not a recall and customers have to eat it because nnot all engine were affected. What initially caused it or what I did wrong??? Not use; I always changed at 75.000 with mobil 1 0W-40 european spec. It's hard to find information about this but it's there and Mercdes knows but will fake it.
Crud, I forgot! For the driver's side, both are UCA nuts (16mm) are accessible in the engine bay, but I had to lay across the top of the engine to get to the rear nut. The pics below show the forward nut first. The only real issue there was getting a wrench down into the web of brake lines out of the ABS master cylinder and coolant hoses from the reservoir. I got one picture of the rear that is decent, and you can see how much fun it is. I actually got the wrench on the nut and then put a few neodymium magnets in to hold it in place while I did the E12 bolt from the wheel well. The passenger side was a piece of cake comparatively, for the rear nut, I took out the cabin air filter housing and it was plainly visible. I had taken out the wheel well liner to deal with the headlight, and the forward nut was almost too easy to get. I actually put my torque wrench on the nut because it was so much easier to do it that way.
I genuinely hope this is helpful. The driver's side took me probably 3 hours, but it would have been less if I hadn't had to hunt these down. The passenger side took 30 minutes, tops, and that includes the time to remove the fender liner.
Last edited by HuskEric; May 6, 2026 at 04:11 PM.
Reason: I double-posted pictures, but there is good info.
Here are a few more pics that help to paint the picture of just how much was involved. This is a pretty good representation of the UCA bushings. This is where I found most of the bump stop for the front passenger strut. This is a ledge in the wheel well. Here is the remainder of the bump stop from that strut. The other one was completely dust. You can see inside the boot all of the dust pulverized from what was originally the bump stop.
Here is the scrap metal from the suspension components (and the water pump)
Mercedes SLR McLaren 722 S Is Extremely Rare Example Modified by McLaren
Slideshow: A one-of-one U.S.-spec Mercedes-Benz SLR McLaren Roadster became even rarer after a factory-backed transformation at McLaren's headquarters.
