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Replacing control arm - will I need tracking done after ?

VenomX

Active Member
Joined
Sep 10, 2024
Messages
75
Location
England
Car
C240 2002
Will be replacing one of the control arms on the W203 ( C240 2002 ) as it is down to metal on the bushing.
Is it likely I will need the tracking done after, or will I have to wait and see ? I don't think the tracking has ever been done on the car ( 36k miles on the clock )

Also. Haynes says to torque the bolt which goes into the subframe 80Nm plus 120degrees. I would probably find it difficult doing the 120degrees accurately ( I do have torque wrenches so that's not an issue )

Any advice ?
This is the arm I will be doing...
ctrl.jpg
 
Yes. Especially as that one looks to have an adjustable angle bushing...hence the egg shaped and not round hole.
 
Will be replacing one of the control arms on the W203 ( C240 2002 ) as it is down to metal on the bushing.
Is it likely I will need the tracking done after, or will I have to wait and see ? I don't think the tracking has ever been done on the car ( 36k miles on the clock )

Also. Haynes says to torque the bolt which goes into the subframe 80Nm plus 120degrees. I would probably find it difficult doing the 120degrees accurately ( I do have torque wrenches so that's not an issue )

Any advice ?
This is the arm I will be doing...
View attachment 166010
For the 120 degrees , mark using coloured pencil (wax type) on the nut and alongside it so you can see your progress
 
Yes, absolutely the tracking will need doing.

You may also need to fit fluted bolts to adjust the camber (if not already fitted).

And although Schaeffler FAG is a decent brand (and Tier-1 automotive supplier), my advise is that you do not buy anything else other than genuine MB or Lemforder.
 
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Also, replace both control arms - the hydrobushes will have leaked and perished on the other side as well, even if it's not knocking metal-on-metal yet.

And the rubber boots covering the ball joints will soon be cracked which is a potential MOT fail.

Not related to the control arm, but while you're under the car check also the drop links, their ball joints' boots often perish as well, and, again, it's a potential MOT fail.
 
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Thanks a lot guys appreciate it. Once I do the job I will get tracking checked. Will any place do? Or should I take it to a Merc independent ( they have a "John Beam" machine there ) But they are more expensive.
FYI: I have done the struts at the front, along with drop links so they are all sorted and I'm fairly familiar with the setup

How come you have to do the 120degrees? Is this to reduce it's impact on the tracking ?
 
Whether you need to take the car to an MB specialist for the tracking is debatable. In my view, any place that has a Hunter machine and a skilled operator, will do.
 
Whether you need to take the car to an MB specialist for the tracking is debatable. In my view, any place that has a Hunter machine and a skilled operator, will do.

Agreed. I had my steering rack/bolts done/changed under a recall. I emphasised that I'd had the car from new low miles careful driver and car drove 100% straight MB assured me before and when I picked up the car it had been "through rigorous checks.." I drove the car out and felt it was not right but put it down to my parnaioa. I even took it to a car park on a very flat surface and I drove it again next day but it definitely pulled slightly into the centre of the road. I rang MB - jokers gave me an appt for 4 weeks down the road we agreed at 2 weeks. (gle)

When I took the car back and waited in their then new showroom, it was a coincident that on the tv screen, an hour after arriving a guy was doing my car. Thankfully, this time they did it properly

Years ago I used Kiwkfit on my then c class - they had a Hunter machine and did a good job

So if they have a Hunter machine and a half-decent operator, you should be ok
 
Someone on YouTube mentioned stencilling around the washer when disassembling, so that everything goes back roughly where it came out, to reduce the effects on tracking. I am not sure if I understand what he means? As the washer can surely only go one way.
I will obviously get the tracking done professionally asap after the job is done.

Any advice would be great, thanks.

I have attached a photo to help detail my question
cnotrol arm.png
 
If you have a bolt with a torx head, it indicates it's a fluted bolt, used for camber (or is it castor?) adjustment.

You must only turn the nut and hold the bolt still, otherwise you can damaged the bolt, the locating washers and the subframe, and the new bush inner metal.

You might need to remove something else e.g. anti roll bar, to be able to get a socket on to the nut to allow correct torque setting.
 
If you have a bolt with a torx head, it indicates it's a fluted bolt, used for camber (or is it castor?) adjustment.

You must only turn the nut and hold the bolt still, otherwise you can damaged the bolt, the locating washers and the subframe, and the new bush inner metal.

You might need to remove something else e.g. anti roll bar, to be able to get a socket on to the nut to allow correct torque setting.

No torx, but I think it is classed as an eccentric bolt. The arm is a " thrust arm "
I know how to fit it but I want minimal effect on my tracking between the time I fit the part and get the alignment done.
 
No torx, but I think it is classed as an eccentric bolt. The arm is a " thrust arm "
I know how to fit it but I want minimal effect on my tracking between the time I fit the part and get the alignment done.
You should see 4 small tags inside the bush hole if it's adjustable and the bolt with have 2 slots running down it's full length. Personally, I'd have it fitted by somewhere that does tracking anyways. Preferably someone that knows the mercedes brand.

Usually the bolt is a normal round bolt that slots in the centre , even from factory.

Picture of camber bolt, showing the slot. Which are actually £32 each from Mercedes eBay shop.

Screenshot_20250123-210329.png
 
I've checked the bolts fitted to my glc , part number

N000000008594. It's a normal bolt with torx head.​


Screenshot_20250123-214013.png
 
You may be on a wild goose chase here... in my case, the old bush was badly cracked, causing distortion. I had the job done by Tony Bones (who sadly passed away since), and he immediately put the car on the Hunter machine and commented that the tracking was seriously off compared to the tracking he carried out just a few days prior to that. The new bush will doubtlessly be firmer and the tracking will be out by a mile. The stencil method might work if refitting the same arm and bush.
 
What do you mean by "down to the metal " ? I have replaced all 4 (twice) on my 203 C class and never seen anything 'down to the metal' . If it's that bad the other side must be on its way out.

There are two bolts available , the slotted one and the one sans slot . They are called 'crash bolts' in some markets as the slotted bolt give the repairer 3 different camber angles to play with , and naturally offers the wheel alignment place the same option . I think it allows a total of 3 degrees of adjustment.

My car had non slotted bolts so thats what went back in and they can only go in the 'neutral' position in the middle slot in the bushing , In my case my two local KwikFit joints both have Hunter machines and one of the guys there is a bit of a car fanatic and was happy to properly set up the first C55 AMG he had ever seen :D .

Get the alignment checked.

By the way , tutorial videos from both FCP Euro and AUTODOC do not mention 120' after torque of 80NM , the addition of 120' would suggest that they are stretch bolts ? , might be an idea to check what HAYNES say by cross referencing with MB WIS.

Or maybe one of our MB workshop owning members can confirm the 120' ?
 
What do you mean by "down to the metal " ? I have replaced all 4 (twice) on my 203 C class and never seen anything 'down to the metal' . If it's that bad the other side must be on its way out.

There are two bolts available , the slotted one and the one sans slot . They are called 'crash bolts' in some markets as the slotted bolt give the repairer 3 different camber angles to play with , and naturally offers the wheel alignment place the same option . I think it allows a total of 3 degrees of adjustment.

My car had non slotted bolts so thats what went back in and they can only go in the 'neutral' position in the middle slot in the bushing , In my case my two local KwikFit joints both have Hunter machines and one of the guys there is a bit of a car fanatic and was happy to properly set up the first C55 AMG he had ever seen :D .

Get the alignment checked.

By the way , tutorial videos from both FCP Euro and AUTODOC do not mention 120' after torque of 80NM , the addition of 120' would suggest that they are stretch bolts ? , might be an idea to check what HAYNES say by cross referencing with MB WIS.

Or maybe one of our MB workshop owning members can confirm the 120' ?

The bush from when I last inspected is very worn, and I can visibly see metal where the rubber is supposed to be - and is perished and cracked. No excessive movement however. When hitting pot holes on this side, it is rough. Struts have been done, and the only things that look worn are these bushes
The front driver is not as bad.
Here is a diagram from Haynes...
control arm.png
 
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There are two bolts available , the slotted one and the one sans slot . They are called 'crash bolts' in some markets as the slotted bolt give the repairer 3 different camber angles to play with , and naturally offers the wheel alignment place the same option . I think it allows a total of 3 degrees of adjustment.

The fluted bolt for my 2013 W204 was A 000 333 10 71. The description is 'ADJUSTMENT SCREW'.

And you don't need to fit it to both sides - only to the side that needs adjusting.
 
The fluted bolt for my 2013 W204 was A 000 333 10 71. The description is 'ADJUSTMENT SCREW'.

And you don't need to fit it to both sides - only to the side that needs adjusting.
Not sure why MB just don't fit them as standard , slotted bolt will fit in all 3 positions. Profit is my guess , as the slotted one would cost a few pennies more to manufacture.
 
The bush from when I last inspected is very worn, and I can visibly see metal where the rubber is supposed to be - and is perished and cracked. No excessive movement however. When hitting pot holes on this side, it is rough. Struts have been done, and the only things that look worn are these bushes
The front driver is not as bad.
Here is a diagram from Haynes...
View attachment 166909
Maybe double check wit MB WIS.
 

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