A209 rear knuckle

[Gav2504]

I have a brake caliper thread gone in my o/s/r knuckle.
I've been trying to source another knuckle on eBay but I've no idea what will fit my car.
There doesn't appear to be a part number on the knuckle. Other than A203 04 05
And the nearside is A203 05 05
I have found one that's off an r171 slk that appears to be marked A203 04 05
The 04 isn't clear but that's what it looks like.
I've messaged the seller to confirm that it's an 04 in the middle but all they did was provide me with a part number of A2033501408 Which means nothing to me.
I sent a 2nd message along with their picture of the number I'm referring to and instantly realised that I was talking to someone sat at a desk and unable to check.

The car is a a 2006 A209 with AMG sports package. The brakes are ate (I think) and the bolts appear to be 10mm.

From what I've seen on the internet some have 10mm caliper bolts and some have 12mm bolts.
So I'm guessing that I can't just throw any knuckle on.
My question is do I have to match it up to one marked a203 04 05 or will any fit. As long as the bolts are 10mm?

 

[Gav2504]

Situated near the parking brake cable.

 

[Gav2504]

After reading multiple threads. I know there's a lot of true Mercedes technical wizards on here. That know everything there is to know if it has a star on the grille.
So, does anyone know what the a203 04 05 means. As it's not a part number but I'm assuming Mercedes didn't put it there purely for cosmetics.

 

[colinallcars]

After reading multiple threads. I know there's a lot of true Mercedes technical wizards on here. That know everything there is to know if it has a star on the grille.
So, does anyone know what the a203 04 05 means. As it's not a part number but I'm assuming Mercedes didn't put it there purely for cosmetics.

Have you done a Google search?

Google Search

 

[Gav2504]

Have you done a Google search?

Google Search

Yes mate. Can't find anything that sheds any light on what knuckle is compatible. Or what that code is for.

 

[colinallcars]

Yes mate. Can't find anything that sheds any light on what knuckle is compatible. Or what that code is for.

That is the part number. Have a look on Partsouq for what is fitted to your car.

Partsouq.com

 

[Gav2504]

It isn't the part number. The part number is 10 or 11 digits.
I've seen a post (none Mercedes) asking the same question and the only useful response they got was " those numbers are probably from whatever casting/production batch produced those knuckles"
So no definitive answer but does make sense.
Which brings me back to my original question. Can I fit any knuckle from various models w203, w209, c209, r171 just so long as it has M10 bolts. Thanks for the link . I'll take a look. So as to confirm my part number but not sure whether it will help much tbh.

 

[colinallcars]

It isn't the part number. The part number is 10 or 11 digits.
I've seen a post (none Mercedes) asking the same question and the only useful response they got was " those numbers are probably from whatever casting/production batch produced those knuckles"
So no definitive answer but does make sense.
Which brings me back to my original question. Can I fit any knuckle from various models w203, w209, c209, r171 just so long as it has M10 bolts. Thanks for the link . I'll take a look. So as to confirm my part number but not sure whether it will help much tbh.

I think that’s the basic casting. I don’t have your VIN but item 10 looks likely, used on a wide variety of cars of the era and may give you a start point.

https://partsouq.com/en/catalog/genuine/unit?c=MB201810&ssd=%24%2AKwG7j562-uHe-M3C-uumteP319DOv7C9vK6Bsvr8z9vHw8HCh5C81vj8-MnfxteRjIa7ssyuuLC_rZuRj9nayt3ax92t__6Bxcuvv7G4r8afk5Lbzdzdxtrx7pCl4P2qtazPz62h8rPgs-b64uWkrery5PC-sba49Pb_6pDv7bv2-s7yqvuv6vyAxKqjrOCqtbzm6vu7pK3pq7K-ueXu-r318fjs4M_28qjgs6qtoqvl7K_q_PC5u7i6v6qjr6O94LOqraKr5eSv6vzzz9utoqvr4a_q_PS_3a2iq_7sr-r886v1AAAAAHEmy0I%3D%24&vid=1860&cid=27996&uid=16492&q=

 

[Gav2504]

Thanks very much for taking the time to help me. It's very much appreciated
It is indeed number 10 in the pic.
I've exhausted eBay for the last several
hours. Nothing I haven't seen dozens of times already. Most are overseas and stupidly expensive. Some are reasonable but listed as left not right. Despite the pictures and description clearly showing a right. So it's 50/50 what would turn up Any messages that I've sent this week (all UK) have all been ignored. Only one person replied and despite looking like the same casting number. It's a different part number to mine. It was for an slk though. Despite being used on a wide variety of cars. It seems there's also multiple numbers. Even though it's the same part. It's blown my mind!
I've decided enough is enough. I'm just going to buy one. If it fits AWESOME If it doesn't then the scrap man will be happy and I'll buy another. Until one does
Condition isn't an issue. As both the bearing and bush are being replaced anyway.

Once again thanks very much for your help. It really is appreciated

 

[colinallcars]

Thanks very much for taking the time to help me. It's very much appreciated
It is indeed number 10 in the pic.
I've exhausted eBay for the last several
hours. Nothing I haven't seen dozens of times already. Most are overseas and stupidly expensive. Some are reasonable but listed as left not right. Despite the pictures and description clearly showing a right. So it's 50/50 what would turn up Any messages that I've sent this week (all UK) have all been ignored. Only one person replied and despite looking like the same casting number. It's a different part number to mine. It was for an slk though. Despite being used on a wide variety of cars. It seems there's also multiple numbers. Even though it's the same part. It's blown my mind!
I've decided enough is enough. I'm just going to buy one. If it fits AWESOME If it doesn't then the scrap man will be happy and I'll buy another. Until one does
Condition isn't an issue. As both the bearing and bush are being replaced anyway.

Once again thanks very much for your help. It really is appreciated

I think the difference will be in how it is machined to accept different calipers etc. for a wide range of vehicles. Have you searched using your VIN for the actual part number for your car?

 

[Gav2504]

Yes, I searched my vin. I also cross referenced the donor vehicle. The part numbers matched. Casting numbers were different but ordered it anyway. Part arrived last week. Side by side comparison appeared to be identical. First thing that I checked was that the brake caliper bolts fit.
Everything looked good. So stripped the new one. Cleaned it up and painted it. Refitted new lower bush and bearing. Later this week. I'll be refitting everything. Back onto the car.