andacb

Hello,

After I bought my 1996 E220 Diesel car, the first thing I noticed was the vibration issue when I was braking and I found out that the left front brake disc was not in good condition. So, I changed both side brake discs, pads and the rotor (where the ABS ring is located) holding them (because some screws were stuck and broken inside, so I had to!).

After driving for a while the vibration issue is slowly coming back (I can feel it during braking). Now I have the following symptoms in my car:

1. The car is very noticeably wobbling/shaking below the speed of 40-50km/h.
2. Although the vibration during braking was gone right after renewing the discs etc (see picture), a month passed and I can feel that the vibration during braking is coming back (same side, front left tire).
3. I believe the car had an accident from left front side before with the previous owner.

My question is: Can it be that the middle "thing" holding everything or the arm holding this "thing" (yellow arrow, see picture) can be no more in good condition or even no more parallel to the ground (is it even possible?)??

Or is it something fixable with a front axle/arm adjustments?

Since the braking vibration is coming back and getting stronger almost every day, something that is also holding the brake discs and caliper etc should be not in order right??

Is there a way to see if this middle "thing" (stick) is parallel to the ground or is connected well to its arm?? (see picture, yellow arrows)

Sorry folks, that I am writing so long and in detail but I am in a desperate situation, because here in Estonia, although we have the highest number of all new Baltic car sales and almost unlimited number of repair shops, almost no one looks to know what they are doing. (Regarding to my experience, no one is specialized, they just try to do something).

So, mostly I am the one repairing my own car. But in this case, I am confused about, how to pin point the right problem.. And it is also annoying to have wobbling/shaking feeling in most of the in city driving experience..

Thanks for any kind of help in advance!

Andac

Plutoe

Typically the wobbling, shudder and shaking comes from bad #5(brake calipers that are not applying equal pressure on the two sides of the rotor)---however you said they were new---do you mean new to your car or really new or Russian imports!!

andacb

they are not brand new but they are new to my car. Although I would really like to agree with you, since this shaking and wobbling is also happening during normal slow drive under 50km/h, I am thinking that something else is wrong that also makes the discs go bad..

Andac

Plutoe

A good double check is pull the calipers and check the pads for uniform or non uniform ware.

Other than the shudder have you noticed any unusual tire ware!!

nelbur

If you can feel the wobble when you are not applying the brakes, the problem is likely with the tires or a rim that is bent. The two items you questioned are the upright and the spindle. I would not expect them to be involved in a wobble. Since you have replaced all of the brake components, and since you feel the wobble when not applying the brakes, I would look elsewhere.

Jack up one wheel at a time and spin it while looking at the rim where it hits the tire. Put something on the ground near the rim so it is easy to see if the rim is wobbling. If the fronts are hard to spin your brake pads may be dragging, (or you have a 4matic). To retract the pads a bit kick on the tire at the 3 and 9 o'clock positions. I back up to the wheel and kick hard with my heel like a horse would. Sounds funny buy it works. For the rears you will have to have the transmission in N or both rear wheels off the ground, and retract the pads.

If the rims look good, suspect the tires. Spin the tires and check the tread for a large wobble or a major out of round. If you find a suspect, swap it with your spare to see if it solves the problem. Swapping the front tires with the rear should change things if a tire is the cause, and swapping tires from one side to the other should also change the feel if a tire is the problem.

andacb

Thanks "Plutoe" and "Nelbur", I will follow your suggestions this weekend definitely.

1. I will check the tires for any wearing issue or misrotation.
2. I will check the rims for misrotation or any other anomalies.

HOWEVER,

After I changed the brake discs, the vibration DURING the braking was totally gone. The car was shaking WITHOUT braking still. It has been a month now and now the car continues to wobble or shake at low speeds BUT at the same time, DURING braking, the vibration and shaking again is very much noticeable.

SO, I have to come to the conclusion that during this one month, the middle cylinder was not having 90 degrees with the arm holding the cylinder and the brake caliper (these green arrows in the picture.) has caused the brake discs to go uneven (unflat) again, because (let's say) the caliper was not parallel to the brake discs and the middle cylinder was somehow angled more than 90 degrees to the arm during an accident? (Please check the picture below)

BUT, is it possible that this "cylinder" (or what it is called) can bend like this from the arm carrying it?

Waiting for any suggestions..

THanks!

Andac

Plutoe

The two degree difference in the king pin, which is a machined casting, which would not bend----look to the large upper metal stamping to pushing/moving the king pin---surely that would show up in an alignment(tow) however I do not know what the spec should be!!

Additionally and I stand corrected however the brake caliper would be at the same angle as the rotor(2 degree), therefore pads would be parallel and not at an angle to the rotor. I still think that your used Russian calipers are the issue

andacb

haha

The thing is, when I got the car, the car was wobbling/shaking when driving slow and also vibrating during braking. After I changed everything except the king pin, the vibration during driving didn't change but the vibration during braking disappeared. After one month of changing the parts, now the car is still wobbling/shaking during slow drive AND started vibrating again during braking and this braking vibration is increasing every week more..

SO, it shouldn't be any parts I put, including the calipers but at some point I want to know, HOW I can check if the king pins health At the end I will try to get one from the junk yard and try it if the vibration during driving changes..

Andac

Plutoe

This car must have been owned by some babuska--------remember the king pin is a cast and machined part---I don't see how it could get bent, it would snap first----before I did anything----try and get the front end aligned---------what is the result and what about the other side---

andacb

I was also thinking about the alignment first, which is the cheapest 20 euros here, but then I was thinking, if this part is somehow not in good condition, then I would make the alignment for nothing..

You are right. This part couldn't be so easily bended, but in this case, how come the new brake disc that didn't cause any vibration in the beginning, could get worse in one month time, if everything there is ok? That was my main logic that is making me think that something with the king pin could be wrong? What do you think?

Andac

Plutoe

Well you are looking at the car. You have driven the car. You have replaced all those parts. The only thing I do not know is the king pin machined tolerences---it can't be a perfect 90 degrees + or - nothing---it has to be + or - something and the difference is included in the alignment calculations\specs--------Never the less you have the mojo(logic) go for it!!

kingbaka

I had a 1996 E300d , salvage , I knew it was wreaked , got it at a great price. The shudder you are describing is common on the control arm bushings , I purchased bolts from MB to get control arm angle within spec , lower control arms , check you-tube , forum on pelican parts , discribes repaires, not very easy , spring removal is needed.