kfriedenberger

Can someone check my VIN: WDDGF77XX9F209870

Valvestud

Once again, any M156 in a car that's 2010 or older is affected.


Thanks,


Joe

AMG893

Will this VIN: WDD2042772F5748393 has engine number 156985 60 063633

(apparently NOT in affected range), and its built 22nd SEP 2010.

Correct?

Valvestud

Correct.

Manofsteelpt

May sound dumb, but will LTH's increase the possibility of popping a bolt? I have an 09 CLS63 btw...

Ingenieur

Imho not unto itself
It does not significantly increase mean effective cylinder pressure

The main factors imo are hours run and more so hours run under high load, eg, that ratio

Manofsteelpt

Im Sorry... does that mean if I'm womping on the throttle a lot, THAT would increase the possibility (no matter of it were the stock or LTH)?

Thank you for your response.

Ingenieur

Yes
The more stress (~mean eff cylinder pressure) on the bolts the more they stretch/relax and fatigue the sooner they will fail

Manofsteelpt

So the LTH would in fact increase the possibility... More sound, more power, more mashing of that throttle, lol :-)

Thank you very much for the help

Ingenieur

Not the headers
But the increased high load use of the car

2 cars one with and one without lth's
If both are used the same the chance would be the same

Manofsteelpt

Yeah, I gotcha... Just sayin, if I got the LTH's, I'd be driving harder more frequently.

Karl901

I wish I had picture of the old bolts, with rust around the head of each one.
Also a picture of the new designed replacement bolts, totally reverse design heads. Basically all the bolts are going to fail eventually. Beats me why MB/AMG is not doing a recall.
Also, MB should be repairing all engines at no charge, this would be at least exceptable!

Ingenieur

If all will eventually fail we would see a much higher percentage by now: 30 to 40%

It makes no economic sense for MB Do anything now since the rate is so low

There are warranty limitations for a reason
They protect the buyer AND the seller
They impose a time limitation so it is not open ended
Can't warranty something forever and can't claim until you actually have damages/failure

And we always have legal recourse

Merc63

They won't all fail.

I have my old head bolts sitting at home. Lots of guys with high miles and no problems.

Jasonoff

I hope not. 73K km on mine and warranty runs out in a couple weeks...

Mark77

I know this is a C63 thread, but I thought it would be best I post my SL63 issue here. It looks like I am another head bolt statistic. I own a 2009 SL63 (Build date is actually 2008). It only has 54K KM, about 33K miles. A week back I had a "low coolant" light come on. My coolant was a quart low and I topped it up. There was no fluids on the floor so I assumed I had an internal leak. Few days later, I checked the coolant and it was low again about a half a quart. There were no other symptoms with my car. It ran smooth and without issue.

I took my car to a dealership today and they did a pressurized test on the coolant system. There appears to be an internal leak as pressure was not being built up. They suspect its the head gasket at this point. I await further diagnosis over the next few day. I do have CPO and it sounds like it will be covered by the Star warranty (In Canada). Thanks you all for the posts as after reading all these posts here, I decided to take the car in right away. Probably saved me from serious engine damage!

BiturboSF

Good to hear that you are covered, be sure to check back in with us after its been taken care of.


I spoke to my service advisor at the dealership & they are aware of the problem. They already done a ML63 & a E63 under warranty, surprisingly no C63's yet. I'm just hoping I won't run into any issues since my warranty just expired 2 months ago.

clk208

Ok, now I'm ready to change the head bolts.
Where did you start to change them? From the middle to the outsight or the other way round?
Is there anything else to take care for? Or only pull one by one and replace it with the new one with torsional moment and rotation angle.


Thanks guys

andy_c63

Does anyone have a copy of the service bulletin?

Mark77

Ok an update with my SL63 after a week in the shop. One of the head gaskets were leaking coolant into the engine. The service department never stated whether it was a result of the bolts or not. But as per the previous service bulletin mentioned in this thread (which was forwarded to the shop foreman by me), they changed both head gaskets, all the head bolts to the new design bolts, all the tappets, and did two oil changes. The cylinders and plugs were ok so nothing else needed changing, just some cleaning. I think I was fortunate enough to catch it early. I WOULD HIGHLY SUGGEST GETTING YOUR CAR CHECKED RIGHT AWAY IF YOU HAVE COOLANT LOSS AND NO EXTERNAL LEAKS. They also found a leak in my radiator and changed that too. Thankfully it was all covered under the Star cpo warranty. Just paid a small $50 deductible. I would guess all the work they did would have probably cost around $10K if not covered. Glad to have my car back!

motoman

The "go screw yourself" seems to summarize MB/AMG posture. The "if MBUSA knew ..a manufacturing defect..." is a bit hard to digest when they can bracket the SN range and replace with different design headbolt. That response is uninformed corporate "speak."

andy_c63

How about all of us file a compliant with NHTSA? If you use the search, you can see that they do investigate if they receive multiple complaints on the same issue.

http://www-odi.nhtsa.dot.gov/owners/SearchSafetyIssues

The only investigation that comes up in the search is for taillight harness melting and shorting the electrical system. I actually had this problem, but it didn't bother me much as it was pretty minor. I guess I will go ahead and file a complaint for the headbolt failure and the taillight issue. The headbolt failure is definitely a safety issue. What if a bolt fails and the engine hydrolocks while driving on a highway?

Can we make this a separate post and a sticky or maybe OP can just put on top of the first post?

Jasonoff

That's the approach I was going to take if it ever happens now that I'm outside of warranty.

"I could have been killed or even worse!"

motoman

Charging hard at MB/AMG over the headbolts is futile, though tempting. Sure , everything will fail eventually. The part that grates is that a headbolt is not a consumable like a windshield wiper or brake rotor. More is expected from a company which "seemed" to have a reputation for quality, but acts like Chevrolet or Ford. Stonewalling and deflecting this issue is very short sighted IMO.

Karl901

Well, maybe it time to show MB with our wallets. Stop buying AMGs!