I have a 2002 s500, and my front driver side wheel makes a loud knocking noise, I took it to german car specialists and they told me control arm bushing needs to be changed and it will cost about 4,000$, so I want to do this myself and I need some tips if anybody knows, or any diagrams from manual or something that shows how its setted up. thanks

 

Hi,
If you refer to the inboard rubber bushes this is a relatively straightforward job but one that you require "special" tools for.
If you refer to the outboard ball joints (which would be my diagnosis) this requires additional "special" tools to push the old ball joints out of the hub forging. They can be very tight!!.

I would suggest that this job requires no step by step instructions except for a couple of tips later on. If you feel you need step by step instructions then i suggest this is not a job for a first timer.
Since you need to remove the control arms, which have taper fittings at the outboard end, and access to these is restricted a particular type of "joint cracker" is required in order to gain access within the space available..
RUST on the join/fixing between the air spring and the track control arm can also be a problem.
Removal of the roll bar helps but is not a step recommended in WIS. However the nuts holding the roll bar brackets DO NOT have captive nuts on them and if you dislodge one you could be in for a big job (part engine removal). "Nut" gets dislodged into an area that you cannot access.
The only things you need to know are:-

Remove the front wheel arch liners to gain adsequate access to the mounting bolts.
"Break" the 3 outboard taper joints.
Undo the air spring bottom fixing. Allen socket buried in base of strut.
When reassembling ensure vehicle is at kerb height (with air suspension at correct height) BEFORE tightening the inboard rubber bushes otherwise isolation (noise and ride) will be adversely affected.
If you want some pics you can send me your email via PM. Advise if you have space limitations.

Don't forget the bushes and joints will cost. Determine this BEFORE yopu make your decision which way to go.

Good luck.
Stuart

 

Find another mechanic. The MB OEM entire control arm and ball joint unit is under $200 at Autohaus Arizona. What exactly are they doing for all that labor. At $100 an hour, this will take 38 hours? Maybe I am reading this wrong and I have the wrong part in mind. I had the ball joint that attaches to the steering knuckle done for $380 out the door which included an alignmentby my local mechanic.

 

Hi Kings.
I'm assuming w220
If it is a "soft" knock" I would suggest that the poblem is the outer track and torque control arm ball joints.
In my view the rubber bushes, except on early cars where the design was subsequently changed, give no problem.
The torque control arm (45 deg forward) has the ball joint as part of the assembly and this is easy to change. Important rubber bush is tightened at kerb height/
The outer track control arm ball joint requires the entire suspension to be removed so as to "push" out the old ball joint.....which is mighty tight!
These get water damaged (rust) due to damaged / worn boots etc. and are a pig to change.
Getting the airmatic lower joint apart CAN be a nightmare due to rust also.
I agree that the stated charge is excessive.
IF you have exactly the right tools and you hit no problems with the lower airmatic connection then I would estimate 4 hrs.....but I have no idea what the official timing is. Anybody know?
However if that airmatic joint causes a problem your guess is as good as mine..........and a new strut is expensive.
Stuart

 

Lower control armbushings are hydraulicon the 140 Ithink on your caralso, and there is a special tool to seat them. I had mine done at MB on my 140 they did both sides the torshion bar links and steering damper $950 out the door.They did confide they broke one (it leaked)and had to redo it but they did remove the control arms. The book shows you can do it by compressing the spring, it is probably easier just toremove it by taking thenut off the ball joint. This included an alignment. I heard you can get a complete control arm with bushings and ball joint from dealer.

 

FYI one Airmatic shock is $1500 at the dealer, I don't know if that includes install. Before I bought mine, the dealer told me that to do all four (hardly ever needed) would be 6K.

 

What city are you in?

 

Thanks guys for all the info, I gott do more estimates and check ups...

p.s. im in Federal Way, WA 98003