Grip Grip

I sold the car before locating the source, but from research back then I think it was an engine idler pulley going bad. I bought the part, but sold the car before installing it.

khutchinson22

Ive already replaced the idler pulley to no avail. I am going to try and swap the drive shaft carrier bearing tonight and see if that helps. Does the drive shaft have to be balanced after doing this? What about the bearing mount? Possible culprit?

Z06Tom

There was a reply from back when this post was originally started about having a bad tire. My car is doing the exact same thing. Makes me nauseous every time I drive it. It will wobble like crazy at certain speeds and seem to smooth out at others. My problem feels like it is in the rear end. I had all 4 tires balanced and it did no good. I decided to try replacing each wheel with the spare to see if I could pinpoint the source. When I replaced the right rear wheel with the spare, it smoothed right out. Pretty sure I have a bad tire...

khutchinson22

So, on a hunch, I decided to resurface the rotors and replace the pads because heat seemed to be a factor with my vibration issue and sure as **** she drives smooth as ever now! I wasn't getting any steering wheel vibration when braking so it wasn't apparent there was anything wrong with the brake system but after putting it all back together it is definitely 90% better than it was.

Crissus

Nice thank you :-)

fireman685

Now that kind of perplexes me... How did that make the car vibrate without it vibrating when the brakes were applied???
I'm glad it solved the problem though.

khutchinson22

So this didnt resolve the problem after all. It seems that every time its in the air (jacked up) for any amount of time it smooths out for a day and then the vibration returns. Some days its worse than others. Ambient temperature seems to have little to no effect. My accumulators seem to be bad and im sure the pulsation dampener is, too. Do you guys think that those components could cause a vibration?

fireman685

Blown accumulators will make the car very bouncy and you'll get a red abc warning going over bumps. At least that's what happened with mine

fireman685

How many miles are on your car?

khutchinson22

Replaced accumulators, pulsation damper and air cell. Replaced rear tires. Repaired all 4 wheels for imperfections. Replaced Trans mount. All to no avail. Next?

fireman685, ~112,000 miles on the car.

Welwynnick

Have you got any under-body panels lose on your car?

If they're not secure, they can vibrate up and down like crazy at speed.

Just a thought.

Nick

khutchinson22

I've been under there quite a bit and nothing seems loose. I'm going to try the driveshaft carrier bearing and mount and see if that helps. I may even replace the flex discs at the same time. Just not looking forward to yet another $500 on the chance that it will fix the issue. There simply isn't much left at this point.

Before I do anything though I would really like to find a set of stock rims to throw on the car for a few days. If it doesn't solve the problem at least I can eliminate it from possible culprits. Unfortunately, it's proving quite difficult to find a set locally that I can borrow.

Welwynnick

"I've been under there quite a bit and nothing seems loose."
Me too - probably more than top-side.

Try swapping them front & rear wheels and see if that makes a difference. The car may behave differently. It won't fix anything, but it will be a clue.

Nick

khutchinson22

Last week i located a bad front ball joint. Im going to replace both ball joints and the other control arms with the non-serviceable ball joints today. If that doesnt fix it i will try swapping wheels front to rear.

Welwynnick

Which ball joint? I've done a lot of mine; may be able to help.


Nick

khutchinson22

The front most lower ball joint and rear most lower control arm. Both sides. Does the strut have to come out?

Welwynnick

Here's a couple of references for the big job (lower arm ball joint):

https://mbworld.org/forums/s-class-w...ml#post6542740

http://api.viglink.com/api/click?for...gspot.co.uk%2F

The strut stays in, but I did remove the upright (probably not essential).

Nick

fireman685

I just replaced both my flex disks and it smoothed my car out dramatically. I had to wait in my rear one due to a wrong part but after I got it put on not only did I lose a horrible noise like something loose in the rear, the car started riding smoother. If you see even a tiny crack in the rubber then replace it.

Dr Matt

fireman, when you say something loose, was it like an inconsistant clunking under acceleration and bumps? I have the noise I described since I bought my car and I've never figured it out even though I've looked at everything......

khutchinson22

Is there a bushing that it Is attached to the lower part of the strut at the lower control arm because it sounds like it's metal on metal. There might be about an eighth to a quarter inch of play. Seems to me there shouldn't be any play at all.

fireman685

I did have that also to some degree. Most of the noise I heard was when I was going very slow like down my driveway which is long and gravel. I thought it was the mounts on the rear struts. What it turned out to be was slack in the rear flex disk. The metal sleeves in it were loose in the rubber. A simple visual inspection made the disk look ok but as soon as you put any tension on it with a pry bar you could see all the cracks in it. It's amazing the difference new ones made.
I still have a clunk sound over big bumps though. I feel it in the floor of the car. I'm wondering how my rear subframe bushings are holding up. The last time I had it on a lift which was last month I used a pry bar on all the rear suspension arms and they seemed tight. I did notice though when I replaced the rear flex disk that when I was bolting the new one up the differential and driveshaft seems out of line like the diff was lower than it should be. When it was all bolted back up the flex disk looked warped and it really concerned me but when I drove it afterwards there were no vibrations so it led me to believe the subframe bushings may be getting weak.

fireman685

There's no bushing. The strut mounts to the control arm via a small tab protruding upwards from a small ball joint and is essential connected with just two Allen screws. Try tightening the screws first and then if you still have movement either you'll need a new control arm or the upper mount of the strut may be compressed causing slack which is very very common.

khutchinson22

Ball joint done. No improvement in the vibration but the steering is MUCH tighter. It basically fixed a problem i didnt even know i had.

khutchinson22

I repaired the upper strut bushing already which didnt help. This play is at the bottom where it meets the control arm. Can the ball joint in the control arm be replaced or does it require the whole arm?

fireman685

You'll need to replace the whole arm. Chances are if that little balljoint is bad then so are the control arm bushings. Turn your wheel all the way to one side and look at the bushings. These can cause vibrations as well.