W124 Advice Needed: Rear Suspension
 

Hi All,
I've been having traction probs in my 300E ever since I got her. Even w/ a fairly light throttle she'll spin up the backs on everything other than dry pavement. And let's not even talk about winter :eek: . (I also have a slight wander at speed, similar to when our 300TE broke a rear spring.) I've gone through 2 sets of good summer tires and a set of good winter tires w/ no change. I also had a computerized alignment (not from the Dealer). All rear suspension is original w/ 135k miles and I have been thinking of replacing some of the Rear Links. I've been under there and I haven't been able to see any one whose bushings look worse than the others or any that are obviously failing. I think I can rule out the Camber Strut because I have zero tire wear. Any other I can rule (Thrust Arm/Torque Strut/Tie Rod/Control Arm Strut) out due to lack of tire wear? How do I proceed? I feel that replacing all four other links (per side) might just be throwing $ at the prob, but they could all be bad after 135k miles.
Should I just take to the Stealership and pay for a diagnosis? (Or take it in for an MB alignment and if there's a bad strut I'm sure they'll tell me.)

have
 

you looked at the little horizontal link that goes from in front of each rear wheel forward and attaches to the chassis? dont know name. on 124s they wallow out the rubber bush and the car handles very wierd. it will turn right on accleleration and left under decel. (or the opposite).

tom w

If you mean the lower one on the front side, that's the Thrust Arm. That is one of my prime suspects. Can't decide if I should replace them all or not. If that one's easy maybe I'll just do that one first and see if it improves.

Any other opinions out there?

Thanks!

The thrust arms tend to wear out before the others. The originals were also a little on the wimpy side, the replacements should be the beefier ones used on the 210 chassis. They'll let the tires wiggle around when they're under torque, which is pretty much anytime you're not coasting.

Have you been able to get underneath the car and inspect the condition of the bushings/yank on the suspension bits?

I've been under there and looked at the bushings and none of them are gone. I haven't been able to get too much movement out of any of the pieces by yanking on them (or the wheel), but I'm not a precision instrument ;) . I've heard that's it's not always obvious, visibly, that they are gone.
Something's got to be done before winter....
-M-

Take a look at my small .mpg videos of a test you can do with the wheel(s) off and the car on jackstands (especially if you feel the need to crawl under the car and have a look while someone carefully mans the breaker bar. If the front wheels are on the ground, be sure to put wheel chocks at both the front and rear of each tire). Make sure the trans is in Park and the E-brake is on, or have a helper in the car with their foot on the brake pedal.

"Bad Link.mpg" shows worn inboard bushings on the upper forward link (thrust arm?).

"Worn Bushing.mpg" shows an overall view of what numerous worn bushings looks like.

What isn't visible is the view from the top, where you can see the wheel toe inwards noticeably. In extreme cases, this will cause accelerated tire wear on the inside of the tread, but some extra wear is inevitable if there's any wear at all in any of the bushings. Be sure to check the inner and outer lower control arm bushings as well. I was surprised to find both of them quite worn on my 86 300E with 155K mi. on it.

Youi'll need QuickTime or Windows Media Player to view the videos

Hope this helps,

Gary

From the video that looks like the control arm stay. I had a problem with my control arm stays... replaced those and the car handles much better. best thing to do is look at all bushings and if any look worn replace that link

Take the wheel off and inspect the bushings. You can use a big pry bar too. Cracking or the bolt nolonger being in the center of the bushing... I've always thought they were pretty easy to detect.
If the car has never had rear suspension work- I"M sure it needs a few links=)

Michael