300D, 1993, 2.5T W124. 138K miles.

The car has had some poor shock/strut return in my opinion for some time. WHen I go over a speed bump for instance I can 'hear' the front struts moving and also the rear more or less bottoms out. With 2 people in the back seat, it totally hits bottom at only a couple MPH speed.

More recently I am noticing what seems to be an increasing amount of what I can only think to describe as sway. I feel a left to right kind of subtle movement. I don't feel it in the steering and not necessarily due to road conditions. More pronounced at higher speeds. To best describe, it feels like the movement I get in any automobile when I am in the draft of a semi-truck or real high wind. But this happens now when I am alone on the road and under no wind conditions. It also feels more of a wag the dog kind of thing from the back end rather than the front end juking around. My totally novice thought is maybe my struts in the front are so weak that it is making the rear feel this way but the rears are gone as well I believe. I am not a shock expert by any means, but I can really feel the bottoming out and weakness although I haven't seen any leaks in the shocks. Steering seems tight and none of this feel in in the steering wheel. It's all in the seat kind of feeling. Tires are getting pretty high miles on them (65K) and also need replacement but I don't have any uneven wear and have done well with the tires (Michelin Harmony's). The tires are starting to make some road noise from overall wear as well as just more info on the entire situation.

My plan. Replace struts and shocks on all 4 corners. Might that fix it? Maybe throw new rubber at it right after that and of course have an alignment done. If that doesn't do it, and if I don't see any obvious bushing or something buggered up, what suggestions should I consider as the next thing to change out in the suspension?

I would look at the Rear subframe bushings

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1999 Mercedes E300TD daily driver sold at 238K miles 106K miles were mine, rust worm got it :-(
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The "wag the dog" description implies that it's not the struts/shocks or tires, but that the bushings on the multilink suspension arms in the rear end have seen better days.

That matches the advice in the "W124 Buying Tips" - that if the bushings and such on that multilink suspension become worn out, it's as if the rear end tries to steer itself and go on independent ops, especially when going around curves or accelerating.

While from the sound of it the shock/struts and tires could stand replacement as well, looks as if the rear suspension needs some attention too.

At the least, getting the alignment checked at a shop that's set up to do a 4 wheel alignment on an MB might show any problems with the rear end - could just be it's been a long time since it's had a proper alignment and adjusting it could set it back to rights.

Here's a link to the buying tips document - check paragraph # 18 in particular -

http://www.w124performance.com/docs/mb/articles/124.1x3_buying_tips.txt

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Just say "NO" to Ethanol - Drive Diesel

Mitchell Oates
Mooresville, NC
'87 300D 212K miles
'87 300D 151K miles - R.I.P. 12/08
'05 Jeep Liberty CRD 67K miles
Grumpy Old Diesel Owners Club

Your subframe bushings MAY be worn out, but what you are describing is the multilink system as mentioned already. This is separate from the issue with shocks which you seem to have diagnosed properly yourself.

I would do the shocks all around and then the multi link and you will probably be THRILLED with your ride!

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1987 300TDT - 195,000 (Original #14 head)
1993 190E 2.3 - 105,000
1981 300D - 250,000

The front upper strut mounts will bottom out and make a metal to metal "clunk" when they're worn and you hit a speed bump, new shocks or not. Are they really cracked? Replace them.

These won't explain the swaying motion, that's other things in play. Any rubber bushings, mounts, links, that are worn in the rear end will give you that wind swept feeling and difficulty keeping a straight line. Tons of posts on these things.

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Cheers!
Scott McPhee

1987 300D

Bad ball joints on the front will make noise that I thought was the strut. Might want to put some lube under the ball joint rubber dust cap to see if that changes or removes the sound before buying new struts.

Good luck!

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You can't always get what you want, but if you try sometime you just might find you get what you need.

Looking at GSXR's posts on suspension works in the "Search ,Advanced" archives
Here and on Benzworld , Superturbodiesel.

He's covered It ALL!!!

In your suspension's case it's age and not mileage.

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'84 300SD sold
124.128

I wonder if I can try that last part of your quote on my wife......

Sometimes I wonder if it would just be simpler to replace everything all at once. On my 91 300D with 99,000 miles, I have replaced shocks and ball joints, but I'm sure everything else is marginal at best. Struts are weeping but not leaking.

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91 300D "Otis", Smoke Silver, 142k mi, wastegate conversion

19 Honda CR-V EX 61k mi
Fourteen other MB's owned and sold
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