W124 Suspension rebuild

[kth286]

the front wishbones had the welded ball joints for both sportline and standard cars with the 320 engines.

there are different wishbones depending which car version you have because the installed bushes are harder for the sportline chassis.

 

[kth286]

Nicks

As you have a suspension problem that you are putting down to springs/dampers; you need to get the car on a ramp with the wheels dropped and the springs removed so that all the suspension can be checked without tension from the springs.

It can be done quickly by someone that has the proper Merc spring compressor and has the experience of previous knowledge.

It is known for bushes to be seized onto the bolts that go through the bushes; and to remove the wishbone for example I had to saw mine off.

When bushes seize, it makes the suspension more solid and you may incorrectly be blaming the springs/dampers.

It was a revelation when my wishbones and rear links were renewed.

Tyre wear pattern can be an indicator of the start of seized bushes, as can clunking noise over bumps.

Only the one bush seizes in the wishbone, but this puts extra wear on the other bush thus causing it knock.

 

[Niks]

So the first step would be to get my suspension system checked out by a someone but for now most probably i'll be looking to get the bushes, mounts and ball joints replaced with new ones.

I went to MB in watford today and did ask about the sportline springs, but they cannot specify what number coils I would need due to the point system being different on every car. The only way they can do this is by obtaining a chassis number of a sportline car very similar to mine and take it from there.

 

[franey]

A Complete (well almost) kit is available for the rear consisting of all the arms and bolts including the camber adjusting ones. Around £120
Then there are the rest of the bushes etc, in the hup, diff mounting and subframe mounting plus the link rods on the torsion bar plus bushes.
An educated guess I reckon the rear would cost no more than £180 without the subframe bushes.

The front is obviously different, the ball joints are cheap enough around £10 each side, the control arm bushes around £20 per side, the torsion bar mounting rubber kit £20

Not really an expensive job and a pleasure to do with new parts.

As others have already stated, a full wheel alignment is a must.

 

[WDB124066]

I have to say when it comes to this type of work I like to use dealer sourced parts. It is just me and I know many of you will say that is silly to waste money, but I just do not trust the manufactures to put all the goodies in the rubber compound that they should to make them work properly and last. I have been to too many manufactures of things to see the shortcuts people take when they haven’t got their customer spec and QA program to comply with!

Incidentally, MB have apparently updated the rear subframe bushes to a new design for the 124, very similar if not the same as the 129 from what I am led to believe. Probably another very good reason to source them through the official channels otherwise you may not get the updated ones

I have also heard that it is NOT a good idea to fit the Nolathane or other similar bushes in the rear at least, as MB designed the whole rear end to move and flex in corners in a predefined way and then return to the nominal position when unloaded, ie a controlled & known deformation effect. Nolathane does not permit the same movement/deformation and makes the cars very twitchy when pushed hard on a track. This has come straight from the horse’s mouth - the horse in this case was an E500 owner who has subsequently replaced all the Nolathane bushes with the genuine MB items and is much much happier.

Make sure you use the genuine MB lubricant when installing those subframe bushes -in fact any bush - as the MB lubricant will not degrade the bush material over time like some other greases might.


I didn't know all E320's had the fixed ball joint lower control arm.

In so far as the points system to determine the correct spring is concerned, I can't help but wonder if it is indeed possible to do a tally for your car, but it is just that they have chosen not to because it is just "too difficult" or "time wasting" for them to sit down and go through the options your car has and tally up the points. Other members I am sure will have been through this exercise and will be able to give you more accurate information on this than I can - maybe do a search and see if it has already been discussed.

 

[Andy_C]

This may be of some interest:

New boxed Mercedes bilstein control arm bushes w124 on eBay (end time 23-Apr-10 09:33:13 BST)

Good luck.

 

[WDB124066]

Some information on Sportline swaybars & things.......

Sportline or "Sportline Plus" Swaybars? - MBWorld.org Forums

 

[Niks]

Guys thats some really good information regarding swaybars, something which I haven't thought about.

I think whats important for me right now is to get all the rubbers replaced pretty quick.

Once that is done, I'll be replacing my shocks and springs then later followed by the sway bars.

By the way, something which I did forget to mention was that I changed the steering rod and steering damper recently and it made a big difference. The steering feels a lot more lighter.

The end result im after is a drive that will feel like a brand new car but more sportier over standard. A good combination of everyday driving, heavy loads now and then with a little track use.

If I have 35mm lowering springs, should I be using shortened sports shocks like the Bilstein B8? I've even thought about the B12 kit too but just worried if it drops the car too low.

Alternatively, I've found out that MB Sportline springs are only 1 inch shorter than the standard ones which gives the car a 21mm lowering (which would be more ideal for me). Again, would I use the Bilstein B8 or B6 shocks with these or use MB Sportline Shocks as well?

 

[kth286]

Nicks

you might get more lowering using the sportline springs depending what size spring pads were originally on the car.

if they were say 3 burls and you changed to 1 burl, you will get more lowering, than just the difference in spring lengths.

 

[Niks]

Currently im using 4 burl pads on my eibach springs and it is still too low. If the sportline springs are 20mm higher by using the same 4 burl pads, then that would be more of a sensible height. However, if I did switch back to the standard MB springs with 1 burl pads, I can fit my whole fist through the gap between my wheel arch and wheels.

 

[w124amg]

suspension creek

Hi , on my w124 prior to the one i have now i had ball joints fitted and it eleminated the noises , as i remember they were pretty cheap as they seperated from the lower arm . id go ball joints and track rod ends and have it looked over whilst having a laser alignment , Beacuse all said and done the roads wont get an better just worse year by year to the point where we will all want G wagons ..

 

[bh13coupe]

Currently im using 4 burl pads on my eibach springs and it is still too low. If the sportline springs are 20mm higher by using the same 4 burl pads, then that would be more of a sensible height. However, if I did switch back to the standard MB springs with 1 burl pads, I can fit my whole fist through the gap between my wheel arch and wheels.

I am in the same boat, I am looking at changing my springs, i dont want to go down the Bilstein B12 route, it will drop my car too low for speed bumps near my home, i am looking at a 30mm drop max and struggling to find the right springs. I have seen HnR and Eibach kits with a 30mm drop but dont know which ones to go for (comfort being the important factor here). i did try std OEM merc springs (comfort in mind) with single burl spring pads to creat a slight drop and the car looked on stilts as stated above. if anyone has the part codes for the sportline springs giving a 20mm drop can they post details or PM me. they seem to be the option to go for.

 

[Niks]

There are quite a few part numbers to chose from but MB sportline springs are subject to the point system, so it all depends what you have in your car that will correspond to the part number you will need.

Ive been speaking to Powerflex in regards to bushes, trying to get them to make me up some custom poly bushes which will last longer and give a more firmer ride compared to the MB ones.

Ive narrowed my search down to the Bilsten B8 dampers with bump stops as these are designed for lowered cars (30mm and beyond). If I decide to go with MB Sportline springs, then I'll go for the Bilstein B6 dampers with a fatter anti roll bar up front and rear, again with poly bushes on them.

 

[Niks]

Update - Hopefully my will be ready today to pick up. Ive had new tie rods put in, new control arms with the ball joints and bushes. Last month the steering damper and steering rod was changed too so hopefully the car will drive a lot better at the front now.

With the help of MB Milton Keynes, they managed to source me a set of MB Sportline springs. Basically, if my car was a sportline with all the current options on it then these are the springs they would have come with. To confirm, they are 1" shorter than standard MB springs so I shall be using 2 nib pads with these.

Im still deciding which anti roll bar to go for, either a sportline or a 500E one.

 

[grober]

Update - Hopefully my will be ready today to pick up. Ive had new tie rods put in, new control arms with the ball joints and bushes. Last month the steering damper and steering rod was changed too so hopefully the car will drive a lot better at the front now.

With the help of MB Milton Keynes, they managed to source me a set of MB Sportline springs. Basically, if my car was a sportline with all the current options on it then these are the springs they would have come with. To confirm, they are 1" shorter than standard MB springs so I shall be using 2 nib pads with these.

Im still deciding which anti roll bar to go for, either a sportline or a 500E one.

When deciding which anti roll bar to go for remember you have to have compatible front and rear anti rollbar characteristics otherwise you end up with a car that has very different roll resistance front to back which may not make for very predictable handling. Increasing roll resistance will make the car sit "flat" when cornering but this may not help the handling on uneven public roads. Sometimes a little suspension droop, body roll and weight transfer isn't a bad thing.

 

[Niks]

Yea I totally agree with that. Still havent managed to find time to pick my car up, had a busy day at work today...hopefully tomorrow now. I'll keep the car in my drive and not use it until I get my sportline springs, then I can get a proper wheel, camber and toe alignment done after these have been fitted.

 

[WDB124066]

Here you go, swaybar data - Ex US.


Knock yourself out.........


Very keen to see what you ended up with and what you think of it. I am looking at doing something similar to you. I want a very small drop in the rear, possibly achievable with replacing the spacers under the springs. I'd also like to take advantage of 15 years of technology in the damper department but would not like the car to be any firmer than standard Sprotline settings. Is this the type of thing you are looking to achieve too with the B6's

 

[WDB124066]

Here is a little information I found on the front lower control arm bushes, especially the rear bush and explains why it is probably not a good idea to fit plastic bushes.

See MB document 33-87067.

Complaint is; Entire vehicle shakes and torsional oscillations at the steering wheel.


Remedy.

"Since March 1987 a modified control arm mounting has been installed on the front axle. The control arm has a two-piece mounting of high-damping torsion rubber elements at the front and rear The distinguishing feature is the rear control arm mounting. This damps the vibration of the vehicle and torsional oscillations of the steering wheel."

Together with this is a sectional drawing of the bush that shows it is not made up of a single piece of material. It looks like there are laminations of different materials within it. Can't post the advice and drawing here as the file size is just a little too large. PM your email address & I will send it directly.

Also I am lead to believe the rear subframe and links are even more susceptible to go wrong if you start putting in non MB bushes.


I am guessing this is just one reason why our cars drive soooooooo differently to others on the road. MB really do put the research in up front and if it isn't right - well then, they make it right through research and product development.


I also did a little research on springs looking for the points system, I found a document that claims AMG used Sportline springs on the 124's - at least from 1993 on. It goes on to say they used different shocks though - obviously.

Send me your email address & I will send the info through if you like.....

 

[WDB124066]

Here is a summary sheet for mods to Front Suspension, see fourth line down.

 

[Niks]

Thats some good information WDB, where did you get all that from? lol.

Powerflex actually took a long time to get back to me so I didnt bother with their bushes. I just ended up using the original MB ones on the control arms so hopefully I wont get any of the problems mentioned above.

The guy from MB in Milton Keynes did say that the AMG cars did come with the sportline suspension system too (sports chassis). He also said there was a full AMG suspension upgrade available for the 124 which consisted of AMG springs and AMG shocks which were made by Bilstein (AMG logo with the Bilstein logo below it in blue). I asked out of curosity if they had any left over, and they actually did in germany at a cost of £2,449 inc VAT!!!

Since im no longer going to have a 35-40mm drop, theres little point in me going for the Bilstein B8 dampers. With the sportline springs, theres going to be a max of 25mm drop (after bedding in), so therefore the Bilstein B6 is what I have chosen as these are designed for lowering springs upto 40mm. I don't think its going to be that much of a difference between the sportline and Bilstein B6 shocks, they should be similar. In all, its the springs which will determine the stiffness and ride height. The shocks is what is going to be doing the compression and rebound. All in all, it should be a good marriage between the two.