Fissure Cracks Brake Discs SL55AMG

[oldplodder]

I havnt found any other threads relating to the brake discs on SL55AMG. Ive done 22,000 on a 2003 model. The discs (worse on front-no bias in the fissures whether NS or OS) display numerous fissures (tiny cracks) upto 12mm long radiating from all of the drilled holes. Infact they began to appear at 15,000 miles. Their initial stance is that I require new P&D ... discs being wear an tear item they decline to replace FOC. They say its the way I drive an indicates overheating of discs. B*&^%cks! I think this is design fault if the discs overheat and crack - Im not driving a Daewoo. They should have manufactured the vehicle with slotted discs as per my DB7GT. Comments anyone? Could the recall on EBC system have had any effect?Taken issue with MB dealer under warranty - vehicle in workshop now ... claim pending. Hey ... as regards ceramic discs ... PLEASE, lets not go there. Cheers x

 

[jberks]

I'd be inclined to agree that its a manufacturing fault. Sure if they'd worn then wear and tear, but wear is that the discs are too thin, not fissures developing. As you say, it's a high performance motor so you really shouldn't be able to damage them even if you had thrashed it!
Plus, if it was thrashed to that extent, I'd expect you to need new pads and tyres quite regularly too. I assume you haven't?

 

[SLinKyjoe]

a, try a different dealer.
b, email the contact address on www.mercedes-benz.co.uk

c, register and see if this guy can help with your information here.

http://www.mbclub.co.uk/forums/member.php?u=6550

he had exactly the same problem on his SL600 and had it fixed FOC. he will let you know what he did.

 

[oldplodder]

Thanks for your support. I drive it and enjoy as its supposed to be (after all, to quote Clarkson " ...why sleep in the garage if you've got Keira Knightley in the bedroom") .. but never taken on track (the car that is) and still restricted. Four new tyres at 8,000 and 20000 - new pads at 15000. Discs look good for 60k except for the fissures.

 

[SLinKyjoe]

the SL600 has had 2 sets of disk replaced and i believe it has only 11,000miles. all with this problem. And i have seen a CL65 with the same problem.

i even got my wheels off and cleaned out the brake dust in mine last week, i was just thinking it may be heat build up being blocked by dust that causes these cracks. altho i dont know, it just made me feel like a proper mechy.

 

[OmniCognateNeutronRangler]

I'm sure Hawk20 will tell you it's a design feature and that every other car on the road does the same thing, but for my money this sounds like another example of MB's fantastic build quality.

I'd definately take it back to the dealer and ask them to show you another car with the same problem to prove it is wear and tear. May be worth getting some advice from the AA or RAC or similar as I believe they have legal departments for this kind of advice. Let us know how you get on.

 

[stumpy]

Other marques that have cross drilled discs, M3s / 5s and 911s to name but two don't seem to have this problem. And if it is a build up of crud in the holes, where in the manual does it tell you to take your wheels off and clean your discs with a toothbrush???

 

[Blobcat]

Cross drilled brakes are very common in the motorcycle world. Seen quite a few bikes with warped disc from over use but never a cracked one

 

[SLinKyjoe]

And if it is a build up of crud in the holes, where in the manual does it tell you to take your wheels off and clean your discs with a toothbrush???

it doesn't. and you need a 2mm drill bit which it also didnt tell you.

mine have no sign of cracking as reported above, but i have heard of it and have seen it on one car with around 20k miles on it.

will ask if that guy ever did anything about it and report back.

I have been told, third party, that you get one new set of disks per 2 sets of pads! but dont quote me on that.

and they are brembo brakes on these cars.

mine are slotted as well.http://forums.mercedesclub.org.uk/attachment.php?attachmentid=659&d=1127143686

 

[television]

Normally drilled holes prevent cracking, not start them, cast iron is a strange metal, very much so if the temper is not correct. nice to know if it is on one or both.

malcolm

 

[stumpy]

Not good enough at any level but on a 100k car it takes the mick. MB should replace them for you with no questions asked.

 

[SLinKyjoe]

Not good enough at any level but on a 100k car it takes the mick. MB should replace them for you with no questions asked.

thats why i linked him to someone who had had them done. I didnt want to quote the measurement, but it maybe 11mm and they get changed. I am still unsure if they know of the reason, but if i find out i will post it up.

 

[oldplodder]

SL55 Brake Discs _ Sensonic recall?

The fissures are visible on all discs but more abundant and pronounced on the front pair - no perceptible difference between ns or os. : and they are fissure cracks not just cobwebs or suface crazing.

Just wondered if the recall on the Sensonic Braking Control could have contributed?

I'll see if can upload some pics.

The toothbrush and drill things have me wondering and may prompt protestations of "get a life" from the bird ... as well as that, I've always claimed no knowledge or interest in DIY .... So if a drill bit suddenly appears my cover is blown. What about those drivers with dentures?

Apart from discs and some minor niggles (swiftly sorted under warranty) its an outstanding piece of engineering : Distronic should be standard on all vehicles with a cruise system. Its only dangerous when you engage cruise on another vehicle that doesnt have it !

PS.
Only other complaint is you cant fit a pair of skis in the boot ... but thats being petty. I think theres a roofrack system available but ... urrrrr can you imagine dropping the lid and forgetting youve got skis on the roof. Maybe HEAD can invent a liquid metal ski that folds in half.

 

[jberks]

I have been told, third party, that you get one new set of disks per 2 sets of pads! but dont quote me on that.

I believe that's standard since they did away with Asbestos in pads. Disks now wear out far more quickly and they do generally replace them with every second set of pads no matter what you're driving.

 

[television]

: Distronic should be standard on all vehicles with a cruise system. Its only dangerous when you engage cruise on another vehicle that doesnt have it !


.

I know its off beat here but that is something I would like, not very many cars around with it (SL500)

malcolm

 

[SLinKyjoe]

PS.
Only other complaint is you cant fit a pair of skis in the boot ... but thats being petty. I think theres a roofrack system available but ... urrrrr can you imagine dropping the lid and forgetting youve got skis on the roof. Maybe HEAD can invent a liquid metal ski that folds in half.

SkiBoard. they go in! I know its new fangled stuff but hey, keep with the times!

And i think the connection for ski holders has a switch connect to the boot switch that prevents your foor from opening once its connected.