jaspirr

Hey all,

I'm looking at buying a 2010 C63 AMG. I've already checked the VIN and it is one of the engines that is in the affected group with head bolt issues. I've done a good amount of research into this but nobody has seemed to answer one basic question:

How widespread is this head bolt issue? 1 in 100 cars? 1 in 1,000? 1 in 10,000? It looks to me from this forum that there are a very small number of isolated head bolt cars. Something like 30? The C63 production number 2008-2011 is something in the neighborhood of 10,000 I'll guess. 30 out of 10,000 wouldn't be that bad. But I'll be the first to admit these are complete guesses gathered from brief forum research.

The reason I'm asking is because I want to know the likelihood that the C63 I'm buying will have head bolt problems. If it's a 1 in 1000 shot, then I'll have no hesitation buying one. If it's 1 in 10, then we have a different story. Thanks.

bhamg

I'll take a shot at this before the usual suspect(s) weigh in. I've only mentioned this to three people on the forum but I will state for the record (and I have it in writing) that there are many more cases than seen here. At the appropriate time I'll be able to make the source and number public but for now, I can't. When I say "many more" though, my extrapolated wild guess is overall, perhaps at a maximum 1-2% to date have experienced head bolt failure, but that is just my guess. That's a lot of cars but the odds are still very much in your favor that it won't happen. I've chosen to pre-emptively replace the head bolts later this year, based strictly on how I use my car but YMMV. That's it. I'm not getting into a pissing match over a figure no one knows but I'm confident I now know as much or more about what that number might be than anyone I've seen post here. And FWIW don't expect the average dealer to talk about this. Even with my dealer (customer) and SA (friend) "mum's the word" is now SOP.

jaspirr

Thanks for that info. If 1-2% maximum is the worst case scenario and the "usual suspects" are going to come in and say it's much less than that, honestly that is not that bad at all.

I come from a Corvette Z06 forum, where those cars were having a similar issue. They had an engine defect from the factory, where the valve guides would wear down and the engine would grenade itself. People discussed it back and forth for years. Many, many people said it was a super rare isolated incident and maybe 1 in 1000 cars were affected. Slowly, but surely, more and more information and research kept coming out and people realized it was a bigger issue. Last I checked, people were ready to admit it was a pretty damn common defect. Nobody other than GM knows the exact amount. 1 in 10? 1 in 5? Potentially even 1 in 2? (My Z06 had the defect, cost $4,000 to prematurely fix it).

Put in that perspective, 1 in 100 looks great in comparison.

bhamg

The information I was given suggests that the percentage of failures might be higher than what I opined but personally, in the absence of more corroborating information, I'll stick with what I said. If I'm able to get a more complete figure later than I'll be able to make a much more accurate and statistically valid projection. Being one of the few here who has actually seen, handled and examined "good" head bolts bulled from a bad M156 though, I expect a rising rate of failures over time. It's gonna happen.

Sidv22

I am looking to do that since I want to keep the car for a while beyond the warranty. Is it possible for you to share the cost and labor time involved?

bhamg

IMO if you're somewhere in the 4's to do the head bolts, lifters and de-carbonizing by a dealer tech who has performed this repair before (and making sure they will warranty the repair even if you have a tune) then that will be a very fair price.

Valvestud

I think your 10,000 is a bit off. I don't know where MB started with the engine serial number, but given the changeover at over 60,000, and the fact that I've seen cars in the low 20,000s, there's at least 40,000 engines our there that are in the range. Remember, it's the engine, not car model, making many more out there than just the C63.


Regards,


Joe

jaspirr

You're correct. I'm completely new to Mercedes so I didn't even think about the same engine used in different models. For C63's, my brief research showed that 2008 had about 500 cars produced, 2009-2011 around 3000 each. That would be about 9500 C63's in that time. The head bolt issue was fixed in early 2011, so it's probably closer to 8,000 C63's affected. That's probably a low estimate, not based on much research, and doesn't account for countries other than the US.

jaspirr

A second question to add to the discussion: What about buying an aftermarket warranty that covers the head bolt issue? If the warranty is less than the ~$4,500 cost to prevent the issue, shouldn't you just buy the warranty then get it fixed under warranty?

turdferguson

FWIW:

I spoke to my local MB service manager prior to my purchase. He's been at that dealership for over 14 years and has seen 1 case of a head bolt issue...

so like I said...take it for what its worth.

Sidv22

Thanks for your response! Did you get it done at a MB dealer?

Back on topic, I think there are many more who are not on forums and dont report it here. When I was at the dealer few weeks ago, there was a lady dropping her C63 off for headbolt repair. she had no clue its a major issue and all she cared was that it would be covered under warranty.
So i think we will start to see more hue and cry since there will be much more cars out of warranty. 1-2 years ago, majority os the 09's and 10's were under warranty and I am sure no one must have given a ***** back then as long as warranty was honored.

whoover

That's exactly what my SA said. Maybe he's the same guy or maybe that's what they're all told to say.

bhamg

Definitely. But if your car has a tune or shows evidence of having had a tune best expect it not to be covered for engine issues.

bhamg

Yes, it will be done at a dealer.

I am Jeff

Your dealership must be a low volume dealership. My tech who primarily works on AMG motors, have informed me that he's replaced quite a few stretched headbolts. If that wasn't the case, MB would not issue a TSD bulletin to the dealerships to replace on a need basis.

Ingenieur

better chance of hitting the lottery or being struck by lightening
out of 50,000 US engines <20 failures (in the affected range)

Ingenieur

the 4 local dealers have not seen any yet

Sidv22

and how did you come to this conclusion? facts or assumption?

w204nyc

My dealership said they did two c63s and a few other amgs.

jaspirr

So I'm completely new to this and I haven't been involved in the likely back and forth arguing that this forum has had. I understand the 50,000 engines. Where did you get the figure that there have been 20 failures? That's the kind of information I'm looking for before I pick up this C63.

motoman

Well as "usual suspect" I must chime in. I tried to treat you all to cross section pictures of old and new head bolt , but for some reason cannot upload and have asked administrators to advise. The new headbolts are made by Kamax (Germany) and are softer (9.8 vs 10.9). Also have sent coolant sample out to see what's floating around inside M156. Could we be doing it to ourselves?

Ingenieur

Fact if the source is truthful
I am limited in what I can disclose
Suffice to say I ain 't sweating it
And if it happens I will be made whole

LFM_Vancouver

I was the 1st case at my dealer. They hardly knew anything about it.

Ingenieur

You here a lot of people claiming failure
How many invoices posted? 1 or 2 if that

People will belive what they like
1 in 10, 1 on 1000 or 1 in 10000
Whatever
Beliefs do not influence what will happen

If you want, sue
Get the numbers thru discovery
Anything else is speculation

MB must not consider it a financial risk since they are not doing anything proactive

bhamg

Well I categorically can state your source is full of ****. Period.