This is such a mysterious car.

A few updates. Got the new tires installed, road force balanced, and a wheel alignment. Now the car pulls slightly to the right 🤷‍♂️. Will take it again somewhere else for alignment, see what they say. What I can see is that the rear right camber is -1.49, which is a bit out of range. Maybe there's some suspension issue that's not visible with the naked eye.

Now the vibration is less visible around 40-60mph, but still there. The wheel is not shaking crazy anymore, which is good.

I changed the differential oil and it was black, thick, and smelly. Looking at it and the way the plugs looked like, it's either original or changed very long time ago. I am not sure if that had a bad impact, but there is more "clunk" when shifting into gear or when accelerating from coasting or taking the foot off from gas. That's a bummer, maybe I should have not changed the oil.

Going under the car I can see two things.

The rear flex disk says Made in W. Germany, so maybe it's original? It has one little metal ring off, but other than that looks good.
I am a bit puzzled though by the part number. It is: 129 411 00 15. I checked through the service records and I found that one flex disk (129 410 01 15) was replaced in 2007. I think that's the front one because it has the new style bolts. The rear one though, I could not find the part number in the forums at all. I can find it on mbpartsgiant, so I am considering ordering both a front and rear one and changing them.

I also tried to look at the center support for the drive shaft, but couldn't see much. Probably that bearing should changed too if I get to change the disks.

When I rotate the drive shaft, there's a little play that I feel/think comes from the differential. Not sure that it's normal or not, I believe it's not. It feels more like what Kent is showing in this video (though I think that pin would maybe not create this play?!? - so probably is something else)

That's a bummer. I don't have the space to work on this myself, so I called a few MB indy shops around. One does not work on these older models but recommended me another one. I called that one and they said we can have a look at it. I hope I can take it there next week.

To me this sounds like a little bit of preventive maintenance would have gone a long way!

P.S. Strange thing, at 95K miles the transmission was changed (M140 270 93 00). I have a lot of old (early 2000s) service records, would be fun to take a few screenshots with the work and prices, maybe when I have a bit of time.

P.P.S: I had a bit of water leaking around the exhaust binding, I think that's not normal.

 

Thanks for sharing the progress of your new project! I was tempted by this car but opted out. Glad someone with skills is bringinging this one back to The Best or Nothing!

 

Late to the party,

I travel for my job, and I was in another country for a month, so missed the start of your thread.

I appreciate your thread, and the pictures. Keep them coming.

You have a beautiful car.

I do have a question, where did you get the TRW upper control arms?

Maybe also mention where you get some of these parts as others may be curious. Our cars like other MBs are suffering from parts not being available.

Continue with your journey,

Thanks,

Martin

 

@MAVA appreciate your support!

A bit of update: took the car to the indy shop and as expected, the front lower control arm bushings are bad. The new Febi parts are not of good quality, so we decided to try to replace the bushings with Lemfoerder (the guy has an old press he used back in the day for W140, which seems to be in good condition and he will try to use it for this job). So now I am waiting for the parts and then will take the car back to get it fixed. I don't have the tools or space to do this myself, and playing around springs is not something I am keen on trying just yet.

Together with the LCA bushings, I will also get the motor mounts replaced and the lower ball joints. It's $$$, but at least I will get it done properly.

After that, it looks like the rear shock upper mounts need to be changed, but new shocks are $$$ (I think I have the ADS version, so will have to check the part number on the shock). Will probably wait a bit on that.

Finally, the door checks need to be changed on both sides (140-720-09-16 -- for normal sedan it's a different part, be careful), so I just ordered those (mbpartsgiant) and will tackle that in an upcoming weekend.

P.S. I got all my parts from FCPEuro, EEuroparts, and PelicanParts so far. The TRW control arms are available at FCPEuro (also one can find originals for almost ~x2 the price at mbpartsgiant). The original ones were TRW with a MB logo stamped, so I though that should be good enough.

 

Don't forget about MBPartsource.com. They are an MB dealer in Laredo, TX and generally give 35% to 40% off list. I use all the sources you listed but also use MBPartsource for MB only parts. Often times their prices are better than the others.

Keep us posted.

 

Are you doing the door stops yourself? I need one on my 99 S600 and am debating on doing it myself.

 

Thanks @quakercity for the suggestion, I'll keep them in mind.

Regarding the door stops, yes, I would like to try to do them myself. I plan to follow a few tutorials around (https://www.benzworld.org/threads/photo-diy-door-strap-stay-r-r.1544211/, youtube) and order a big trim kit online to make sure I have all the tools required. I think it would be more cost effective and something I can do myself rather than taking it somewhere.

Will let you know how it goes.

 

Just have the correct spring compressor. Do NOT use a rented unit.

If you are not willing to invest in the spring compressor, do not do the job your self.

This is super dangerous work.

I have a thread I started a decade ago or older on the subject.

On the LCA(lower control Arms), replace the bushing instead of buying a aftermarket arm as the bushings are installed out of phase( wrong rotational angle). Every aftermarket LCA is wrong, or buy factory MB LCA’s

Martin

 

@MAVA yeah, I will not do it myself. Plenty of other stuff I can try to do myself.

@quakercity - I found a youtube video showing how to remove the panel for the coupe. Looks simpler than the sedan where most tutorials and videos show that you need to remove the wood with the seat adjustment, which is tricky and the wood can break. Apparently, for the coupe it's not needed, so I am going to try that. Waiting for the parts to come before taking the panels down.

 

FYI on the rear upper shock mounts. I had the left side go bad. The mount is separate from the shock. After removing the shock, It can be unscrewed from the top of the shock BUT it is very difficult (in my case impossible) to remove because of Locktite. The screw part of the shock twisted off. I was reluctant to use to much heat on the shock. I had to have a bolt welded to the top of the shock ($30). I shaved down the head of the bolt about half before it was welded so it wouldn't raise that side of the car...I can't see any difference in ride height. Then just reinstall the shock. That was 2 years ago. No problems.

BTW, you don't need a spring compressor to remove the shock. Just use a separate jack to raise the rear suspension which compresses the spring. Then the shock can be slipped out. At least it worked for me.

Also I use the term shock when strut might be more descriptive for my 93 coupe.

 

Thanks @PoNoMo for your insights. Unfortunately, I don't have the tools for welding or trying to heat & unscrew the shock top mounts. I will wait on those a bit and might bite the bullet and order new ones. I have not decided yet - still waiting to hear from the indy about the order for the LCA bushings and have them replaced.

Tried last weekend to take off the driver's door panel to replace the door check strap with a new original one (which to my surprise came already greased) but was unsuccessful and did not want to force it. I have this image with how to do it (see first pic below), but I think it's for pre-97 models. I took 1/2/3/4 out, and the one screw around 5 that's under a little plastic cover in the rest and then under the arm rest. Then I managed to pop all the lower / left / right rivets out, but it somehow felt that it's held from the top and around handle or around seat adjustment. In this Youtube video, it comes off pretty easily so maybe I just need to be a bit more firm and getting it out from the top:

I have another diagram (see 2nd pic) for 1997+ models, but it only shows it for the sedan and I think the coupe version is different. Does anyone have the version for the coupe?

 

Got the motor mounts replaced, the LCA bushings, and the lower ball joints in the front suspension. Unfortunately, that did not fix the vibration issue so back to reading and thinking what other stuff to chase down!

The shop managed to change the mounts in 3h but they had to take down the exhaust on the driver's side for easier access.

A noob question: how do you open the hydraulic reservoir cap? I don't seem to be able to take the line that is connected to the cap off.

 

Today I changed the rear shock (1403209613) on driver's side as it had a loud clunk when going over bigger bumps. As expected, the top shock mount was wiggly, almost as bad as the one that @Aerosurfer showed a few years back.

Even worse, the bottom mount was also bad and the rubber gone. Found another shock in good condition on eBay and went in person to see it, and overall, I am happy with the result. No more clunks!

I followed mainly this thread here to do the replacement, but one thing I can add is that in the coupe it was very easy to pull a bit of the carpet in the trunk on the left, which gave enough space to access and remove the top nut. It's really not needed to take apart more stuff there, just that area (mine even had a hole for easy access).

Another good tip is to use some cardboard (I used the largest moving box from home depot) under the car for when removing the shock's hydraulic line as the oil will spill everywhere until you manage to separate the line from the shock line. I also used a big oil pan catcher (it's for 4 gallons), which caught everything. Consider also putting some rags around that line as oil can spill all over that frame bushing and even the exhaust.
Pro tip: once the old shock is out, don't forget to compress it to remove all the fluid in it, otherwise depending how you store it, you might get oil everywhere. Ideally, use a screw/plastic cap to block the oil from getting out.

When installing the new rear shock, I had to wiggle a bit to get the two lines together again, that was annoying. Once I did that and reconnected them, I used the floor jack to push up the control arm so that I can put the bolts to the bottom of the shock and torqued it to 100 NM. The top nut needs 40 NM.

After all this, I took out the fluid in the SLS reservoir and replaced with fresh new fluid from MB (000989910309). Then I started the car and pushed a few times in the back to get the fluid going, then topped the reservoir again and checked that the level is between min and max. Took it for a ride and then checked again the levels. All in all pretty straightforward, but it can get messy.

Now I need to do also the passenger side. I hope then I can also change the SLS reservoir filter, but I could not figure how to take it out just yet.

P.S I am thinking to recondition my old shock, but 1403200944 (the top mount) is not available anymore / backordered, and fcpeuro has it priced at $200. Will see if it will come back but I doubt it. The only ones one can find now are from URO, which might be less qualitative.

 

P.S I am thinking to recondition my old shock, but 1403200944 (the top mount) is not available anymore / backordered, and fcpeuro has it priced at $200. Will see if it will come back but I doubt it. The only ones one can find now are from URO, which might be less qualitative.

I do not think the bottom mounts are available. I saw something where someone made a replacement. I had the top replaced years ago on one of my cars, but when the bottom goes you have to replace the whole strut.

 

Love driving the car. It is really fun!

Wanted to share an update here.
Been waiting for parts for a while, but now they are slowly arriving. I decided to buy only genuine MB parts as I don't want to do the work again anytime soon (which might be needed with lower quality parts).

Will try to refresh the rear suspension a bit. The outer bushing on LCA is gone, got the new ones (2043250027) and will buy one of the tools to press them in and out. Mercedessource used to have one ($80) and didn't order it in time, now it's gone from their website. Other options are Baum, CTA, and other ones. Ebay Europe has them for 35 euros. There is one place to rent (it looks like a CTA one) for $20 a week.

Also got new rear tie rods (1403503153), new sway bar links (found original MB on partsouq 1403203589), and sway bar bushings (1403261781).

A few weeks ago I replaced the rear left spring with a new one (1403241904 - got the las one available...) and also replaced the rubber pad as well (1403250184). I did use a schwaben spring conpressor and it went well.

I also got new flex disks from MB (1294110015) but they did not come with screws so I will reuse the old ones. I think that should be ok? The front disk has the new style screws as it was replaced many years ago, but the back one might be original. Got the center support bearing too (0089814325) but the support itself is NLA. Will see when I take down the drive shaft to change the flex disks if the support rubber is still good and if I can only change the bearing.

Has anyone replaced the rear tie rods? Do I need to be aware of anything special or it's mostly a drop in replacement? What about eccentric bolts there?

 

As far as rears go, the lower bushings are available here Mercedes Benz S-Class W140 1992-1998 New Suspension Rear Left/ Right Shock Absorber Bushing (1403209313)

But you can buy an entire rebuilt shock pair from them for $850. Given that the oem mounts are 150 or so and nla and even the URO's are 90, its only 200 more for a completely rebuilt shock without having to press anything or cut/torch the old mounts off. Now, whether those are URO parts used used in the rebuild IDK, but its likely worth a call.

 

As far as rears go, the lower bushings are available here Mercedes Benz S-Class W140 1992-1998 New Suspension Rear Left/ Right Shock Absorber Bushing (1403209313)

I think I remember I bought the lower bushing from this source and my mechanic had to rethread it or do something t get it to fit.