E420 Creaking Noise in Slow Turns
 

I'm getting a creaking noise when I'm in a parking lot, turning the wheel left or right and driving less than 5 m.p.h. (e.g., when going through a drive through). I figure it's either the steering damper or the control arm bushings/ball joints.

I'm going with the steering damper first, because the dealer has it in stock and will sell it to me for $55. The control arms are substantially more expensive. Last year, just before my 400E was totaled, I replaced the steering damper, because it was making a single clunk sound under the same circumstances.

Anyone experience a similar noise and figure out what was causing it?

My S320 it was ball joints in exactly the same situation. Tie rods as well....

Great. The tie rods have been replaced. I'm not looking forward to dropping the control arms on this one. What was Mercedes thinking when they designed it so you couldn't just replace the ball joints alone?

Does the car also creak when going over bumps at slow speeds?? Take and pull the top of the wheel from side to side. There should be no wobble in it. If there's wobble, ball joints are in your future.
On the 140 ball joints are easy to replace...
There are threads where guys replaced their ball joints on a 124 body car without taking the springs out, or dropping the arms. I posted in one a while back.... He had a nice pictorial on how to do it as well...

No creaks when going over bumps slowly. The last time I checked, there was no play when I tried moving the top of the wheels from side-to-side.

For some reason, the E420's ball joints are built into the control arms, so you have to replace the whole thing. I read a post where the 140's are so simple--as they all should be. Can't understand why MB did that.

Can't hurt to try the shock first....

You could also try spraying oil or graphite into the ball joint... If the creaking goes away, that could be your diagnosis...

Thanks. I'll try that. I read a post where someone used a hypodermic needle to get the oil inside the rubber ball joint boot. I'm not sure if you can buy those over the counter, though.

needle... any farm store.

Get one with a big enough bore. If they are creaking.. you probably need to just replace them=0)

Thanks. If they are the problem, I will definitely replace them. At $531 for two control arms, I want to make sure they are bad. I'm curious, what's the reason for the eccentric bolts on the control arm bushings?

To adjust caster and camber, IIRC the rear bolt effects caster and the front bolt changes camber.

But I could be wrong - it might be the other way around.

If I replaced the control arms, would I need to have the front end aligned because of this?

Almost certainly you would need an alignment.

When you remove the eccentric bolts mark the position of bolt head with respect to the mounting cradle on the uni-body where the control arms attach to the uni-body. When you reinstall the new control arms put the bolts in the same orientation as they originally were and you should be in the ball-park for chassis alignment.

On my car this procedure got my pretty close but there was a noticeable improvement after I got it back from the alignment shop.

Also don't forget that the control arm bolts have to be tightened with the vehicle loaded in a 'ready to drive' state.

Great advice. I didn't know any of this. Thanks!

FYI,

$531 for the set? Sounds a bit high... they were $197 last month. Check your suppliers...