lungs414

My 09 4matic has a kind of chatter in the steering wheel. Strangely, it only happens immediately after starting the car and the tranny is engaged and I turn the wheel quickly as in pulling out of a parking spot. Then it doesnt happen again until the car is off and I repeat the procedure. When the service assistant spoke to the shop forman he says it is normal because the rack is electronic, but I don't buy it. He says if they swap the rack out they have to send the part back to benz and if they say there is nothing wrong with it they wont be reimbursed for the repair.
Unfortunately it doesn't happen all the time.
Any suggestions are appreciated.
Thanks

Em Bee Lover

03.11.2011 I posted this---My 2007 S550 4Matic.#117123 built. With car not moving, when I turn the steering wheel to the left, at about 3/4's of the turn a very audible wheel chatter/wheel hopping starts. Turn the wheel back to the right and the same thing happens. It is felt in the steering wheel.

Kinda scary, plus this should not be happening in any car, much less a six figure one. Head mechs at two separate MB dlrs. felt it in the steering wheel and saw the wheels hop. Neither had seen this nor could say what was causing or what to check. Anyone had this? Thanks.

Is this what your's is doing?

I also posted this about that time.....After starting and putting in gear, if needing to turn left or right substantially or to where the steering wheel will no longer turn vs. simply going forward, there is a "chattering"/hopping in the front wheels as the steering wheel gets close to the end of its travel.

That is, the wheels/tires literally skip/hop/chatter. The skipping can be seen in the tire/wheel and felt in the steering wheel. This is on blacktop and cement. Haven't tried on dirt, grass or other surface.

This happens inconsistently. It happens as the steering wheel is getting to the end of its range of motion. Turn the wheel the full opposite and it again happens near the end of its travel. There is no skip/hop in the middle of the turn, just toward the end of its limit.It happens whether in park, neutral or gear. I cannot sense it happenning when vehicle is actually in motion or at speed. Plus, move the car but a few feet and turn the steering wheel from stop to stop and it often won't do it.

There is no "play" or sloppiness in the steering and the road feel is solid. Factory original 18" Continental "Conti" tires on stock wheels. Ex. MB dlr. head mech and now an indie has never seen and is lost for an answer.

I'd like to know if it is. I got no info via board, except one suggesting bushings. It's still doing it. Not gotten worse, just darn anoying. Thoughts?

lungs414

Finally. The motor mounts were replaced and it is fixed.

Em Bee Lover

Is yours 4Matic or rw drive? I replaced all mounts and that didn't impact/change the wheel hop or chatter.

lungs414

It is 4matic. My prob started about 25-30k miles, and got progressively worse. I went to an independant repair shop that I use for repairs on a VW I own to ask his opinion. He is a former MB foreman and told me it is common for Motor mounts to be a problem on these cars due to enormous weight in the front of this car. Makes sense I guess.

Em Bee Lover

I am honestly very happy your problem is fixed. I had motor and transmission mounts replaced less than 10,000 miles ago and there's still vibration felt in the steering wheel when at stop, w/ car trans. in "d", drive. Not noticable while driving and steering is solid; no veering or vibrations. I guess I just tolerate the annoyance. If anyone else has ideas, please share. Thanks.

famous550

Tired of my S class. I have so many problems now i barely even drive it anymore. Dropping it at the dealer for them to keep it.. Lol

new550

Anyone ever find out any more on this....I have same chatter as described, I have had the motor mounts replaced recently but unlike described above, I am having some "sloppiness" in the steering....seems to happen when I hit a small bump or rough patch of road....dealer checked ball joints, one was bad and replaced, but it just doesn't feel right anymore....I wonder if the wheel chatter is related?

new550

Update - Dealer checked everything out and says Ok, but said tires (conti extreme contacts less than year old) were the issue. I am glad suspension is ok, but I still think steering not tires is problematic. Any experiences with steering racks or the like on 2007 s550 4matics? Just seems loose and dances a bit on small bumps.

new550

Another Update - took the car to a flat gravel lot to test if the hopping or chattering was simply the tires skipping on the pavement. Not the pavement, same chatter in the steering wheel with tires easily rotating on dirt or gravel.

Anyone familiar with steering rack or hydraulic valves or adjustments on these? Especially interested in 4matic advice?

Thanks!