W204 front brake caliper movement

[Sonny91]

hi all,
I have a late 2007 w204 320 cdi sport
This issue has been cracking me up last couple of month
Firstly i started hearing a knocking/clunking noise from the driverside wheel so had a quick look and was certain it was the antiroll bar as the bottom link was covered in grease and it had abit of play
So my car was due its service which i did myself around November and whilst doing the service i replaced the anti roll bar and also done new pads all round.
So after the service i take the car out and at first i thought problem solved and then i heard the noise come back, so the next day wheel off again and i used my breaker bar to check for movement around the area
I found alot of movement in the wishbone so i decided to replace that but still no luck
At this point its really starting to get annoying so having 2 weeks off over christmas and alot of browsing on the net i decided to have a look over the caliper and found a little play
I then noticed if i have the car in reveres, press the brake and release i could here the clunking so i got the mrs to do it whilst i inspected and it looked a mess
When the brakes where pressed hard as the car was moving backwards i could actually see the caliper move back with the disc about a inch so theres some serious play somewhere but im struggling to pinpoint where
They are floating calipers so really only held on by the 2 bolts that go into the sliding pins
Which where pretty tight, that tight i decided to tighten the top one abit more and snapped it so the car is useless till i get new bolts
After reading somewhere these are only a 1 time use anyway which i was unaware of
Having more of a look i also found abit of movement on the caliper pins where the bolts slide through before bolting onto the caliper frame but not sure if they are supposed to have a little bit of movement
Any help greatly welcome i need to get rid of this clunking

 

[Sonny91]

And sorry by movements in the sliding pins i dont mean sliding like they are supposed to but if i hold them i can move them back and forth

 

[alecmascot]

After reading somewhere these are only a 1 time use anyway which i was unaware of

The one time bolts are the ones holding the caliper carrier to the strut.....

 

[grober]

Mercedes-Benz W204 Front Brake Caliper Replacement - (2008-2014) C250, C300, C350 | Pelican Parts DIY Maintenance Article

 

[Sonny91]

The one time bolts are the ones holding the caliper carrier to the strut.....

Thanks for your reply
Ive ordered new bolts and slip pins as they come together and not expensive
Do you think this could cause that much play in the caliper ?

 

[Sonny91]

Mercedes-Benz W204 Front Brake Caliper Replacement - (2008-2014) C250, C300, C350 | Pelican Parts DIY Maintenance Article

Thank, this was the guide i found when i realised the bolts had to be replaced

 

[alecmascot]

Do you think this could cause that much play in the caliper ?

I find it hard to believe there could be 25mm of radial caliper movement as the car tries to move forward and backward without something being broken.
Worn guide pins will just give a little bit of play.

 

[Sonny91]

Yeah i can agree with you there
Ive checked everything else and all the bolts seem solid,
Ill fit the new parts and holpefully that resolves it but if not will probally be a trip to mercedes

 

[grober]

Thank, this was the guide i found when i realised the bolts had to be replaced

Having checked again the pictorial guide I referenced may be a different design of caliper from those found on your car. The bolts and pins appear to be combined in that design -hence the need to replace them each time. For the small bolt and separate pin design shown in the video below only the small locking bolts need be renewed. I don't think these are stretch bolts as such but come " encapsulated " = with thread lock compound on their threads- you could probably re-use them if you were to recoat the threads with high temp thread locker. Quite often the replacement pads come with these small bolts included - the MB ones do. The bolts that attach the caliper to its support bracket on the hub are heftier items and again when new they come with thread locker on the threads. In my experience garages tend to re-use these larger bolts with thread locker when removing/ replacing the caliper support bracket. If youa re experiencing that degree of movement on the caliper somethings worn or broken.

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[Sonny91]

Having checked again the pictorial guide I referenced may be a different design of caliper from those found on your car. The bolts and pins appear to be combined in that design -hence the need to replace them each time. For the small bolt and separate pin design shown in the video below only the small locking bolts need be renewed. I don't think these are stretch bolts as such but come " encapsulated " = with thread lock compound on their threads- you could probably re-use them if you were to recoat the threads with high temp thread locker. Quite often the replacement pads come with these small bolts included - the MB ones do. The bolts that attach the caliper to its support bracket on the hub are heftier items and again when new they come with thread locker on the threads. In my experience garages tend to re-use these larger bolts with thread locker when removing/ replacing the caliper support bracket. If youa re experiencing that degree of movement on the caliper somethings worn or broken.

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Mines are the longer bolts in the first tutorial you posted, the starting point is to replace the bolts and pins and take it from there
There is nothing obvious broken that i could identify and i had a good look around so fingers crossed this will finally be resolved