scottw

2007 c230 ss with manual transmission, 223,000 miles.

Car wobbles at highway speeds and now even below. It is NOT bouncing, braking, verring or any of that stuff. It wobbles like wind buffetting and you can feel it in your seat of the pants, so it should be at the rear.

Entire suspension geomatry has been checked. Wheels were straightened twice. MB Manhattan had the car for 2 weeks and the service supervisor and I drove it. I ended up getting new wheels, but it still does it.

Any ideas?

PS. MB Manahattan was great. They even refunded the $600 for the wheel straitening. They stepped and went out of there way. Love that place.

tommy

Wheel bearings? Parking brake assembly?

I'm assuming by "suspension geometry" you mean all bushings, links, etc. have been checked out?

If you're looking for good non-dealer work in North Joisey, Bell's behind the Fashion Center on Rte 17 is awesome.

KSKarl

If it's a wheel or tire problem you'll feel the frequency change with road speed. Had a tire with a slipped belt once that had a little sideways jog that kinda felt like your description. But you've changed wheels and tires so that's ruled out.
Also had slightly bent axle in my El Camino. Again I could feel the frequency increase with road speed. But unlikely with the independent rear suspension of the Mercedes. Easy enough to check for runout with the car on a lift.
If it's random, not varying with road speed, there's something loose in the suspension. Some cars mask the looseness when the car is on a lift and the suspension is at full droop, but your specialist who checked it out should know those tricks better than I do. Could even be shocks wearing so you're feeling the bumps in the road differently that you're used to. How many miles are on the shocks?
Usually if it's a wheel bearing you can hear it before feeling any wobble.
Just a few guesses. Wish you well with your search...

AutohausAZ-Mike

Are you getting any kind of weird noise and if you are, is it getting louder when you accelerate?

jogger

did they check drive shaft/flex disks?

gtrecordings

sometimes warped rotors can be felt

Boom vang

I bet it is the parking brake assembly under the rear seat that is rusted and not fully releasing. This is a common problem with these cars if you live in the rust belt. The symptoms are exactly how you describe.

Did they check the drive shaft hanger bearing?

scottw

Thanks for the replies.

MB Manhattan service foreman drove the car with me today and he felt what I felt. He described it as skating in the rear. He had it up on the lift and showed me that the left rear shock was weak, as he could lift the wheel up a bit. I did it too, but not nearly so much as he. He explained that there should be no movement at all. so, he will take the shocks off and do a test to make sure. He said this is likely the cause. I sure hope so. I had a passanger in the back seat the other day, and they said they were scared of how the car handled, so I knew it was time to deal with it once and for all.

On the parking brake, I mentioned this to the service forman as he was driving. He said that I likely could fix it by tightening up the linkage under the seat. I really do appreciate the posts on that one.

I have to say. MB Manhattan is really very good. I came in today without and appointment and they jumped on it. The had reimbursed for past work that did not solve the problem and turned out not to be needed. They are a standup outfit. It has a huge service department with room for 400 cars at a time. It is pleasant and efficient. And their diagnostic charge is the same as the MB dealer in Ohio and MI.

Boom vang

re parking brake

It is not that you have to tighten it up, it is the lever that freezes up with rust and have to free it as it will prevent the brakes from releasing all the way

https://mbworld.org/forums/c-class-w...ustment-2.html

scottw

The problem was finally diagnosed as bad front sway bar bushings. They showed them to me and they were gone. The local repair shop in Linden NJ unbeknownst to me tried to fix that by putting a piece of rubber hose in the bushing. MB showed it to me. They said the rear struts not too bad after doing some off car bench testing.

scottw

But the help I really need to know is how to remove the rear seat cushion. I know it comes out because I have seen it when having the fuel pumps fixed. But the rear seats do not fold, and I cannot figure out how to remove.

I can life up both parts of the seat by the doors, but the middle section by the seat belts does not move up easily. I do not want to force it. There must be some trick to it.

king05robert

Hey Dear How was the lever is freezes...?????

KSKarl

Rust freezes the pivot pins in that center lever, not a cold thing. English can get confusing.
Once you get to the lever like it shows in the link, spray the pivots with penetrating oil and work the brakes a few times to loosen it up.

MiataMan

Did front sway bar bushings really cure your symptoms? You're satisfied the issue is resolved? If so then why did MB Manhattan focus on bent front wheels? Did they really straighten them or just charge you for straightening them after they found they ran true? Why didn't they refund the price of the new wheels when the old ones were not in need of replacing? I don't think you mentioned replacing tires. Wouldn't rebalancing and then replacing tires be a logical first step before straightening wheels? They tried to sell you new shocks in the rear? If in fact the "entire suspension geometry had been checked" then why didn't they noticed non-standard rubber in place of actual sway bar bushings.

So much doesn't add up. Sorry but to me it seems like this dealer was as clueless as many of the others and not at all shy about charging for whatever diagnosis path they choose to go down. So in the end, what was the total bill - including ALL charges for ALL wrong guesses?

I honestly do hope you are loving your great car again in spite of this bad experience!