I have some info (solid numbers) that sheds new light on the possible number of M156 headbolt failures, this given to me by an M-B employee. I don't have and haven't asked yet for permission to post it here but it'll allow us to make a more accurate estimate of the number of failures to date. I actually might not ask to make that public until I get the job done myself on a pre-emptive basis...perhaps late this year. Regardless, it's interesting to know...

 

i'd say for every 1000 63 motors applicable, 25 failed.

just my guess.

 

This is probably a dumb question but does the sl63 (M156) use timing belt or timing chain? I'm pretty sure it's timing chain but couldn't get a sure answer. I google it and I'm surprised I couldn't find an answer for this simple question.

 

Chain

 

thanks

 

Hi Guys i got a question . i have 09 c63 vin last digits F242570 just wonder if i am affected . 5 days ago i start hearing clicking sound from my engine the has 50K. it sound like its a bad lifter. i had similar issue on my 1.8t with 120K. anyways since i have MB extended warranty i took it in. after couple of days the Mb dealer told me that i have a faulty camshaft adjuster. now is it in any way related to the head bold issue. and also if i tell them about it, is it going to be covered under my ex warranty ?
thanks

 

A little research on the forum would have given you direction here: All 2010 and older and some early 2011s are affected.

 

can you tell me is it covered under MB warranty ?

 

Not unless you have an active power train warranty. If out of warranty and you have a failure it's on you, altthough some have been successful sharing cost with MBUSA.

 

i see, i still have 10 month of extended limited warranty, i wonder if that includes power train or its a different one .

 

There are two separate service bulletins and you car is affected by both. Head bolt failures and excessive cam wear. The head bolts are not properly designed and can corrode and snap at the head. This causes the head gasket to fail letting coolant into your cylinders. If not spotted in time you end up with hydro lock and a blown motor. The other involves the lifters with cause premature cam wear. The lifters should be replaced by ones designed for the SLS63. While the cams are out they should be checked for excessive wear. As long as the cams and lifters are out, you might consider having the head bolts and gaskets replaced.

 

Also, if the headbolts are replaced by MB, the lifters are replaced as part of the process.

 

yes, you are covered. prior to purchasing my '09, i double checked with MB, not the dealer, if these issues would be covered with the CPO extended and they said yes. so, the first year CPO, obv, then the additional two years i purchased in addition all covered this issue.

 

Have another 2011 VIN: WDDGF7HB0BF553135


thanks in advance!

 

Never seen the TSB for the excessive CAM wear - can you post or point me to where it is posted please.
Thanks.
K

 

me two thanks

 

could you please direct me to above service bulletins thanks

 

I have this one...for head bolts...
K

 

my car is already over 100k. do you think it's still worth it to do the headbolts preemptively? i am probably going to keep the car unless some generous stranger comes along and makes me a ridiculous offer.

 

Imo, no. You would have likely already seen it if it was going to a major issue with your car. Not every affected car is necessarily a time bomb. The bolts were prone to failing, but not guaranteed. I'd keep an eye on the coolant and if you do see an issue then go ahead and get it checked out further.

 

when you say keep an eye on the coolant, you mean the low coolant warning? i haven't had any issues, but i did recently get my coolant thermostat replaced (triggered a CEL) and i noticed that it started running hotter (90C on the cluster).. before replacing it was reading something like 60-70C (don't remember exactly, but it was below the halfway mark all the time, versus now where it's slightly above), but assuming that was just because the thermostat went bad.

 

The level of the coolant, because if you have a headbolt leak you could be losing it to the outside of the block or elsewhere.

 

Not affected.


Regards,


Joe

 

the temperature level is always above the halfway mark. Mine only have less than 8k miles and it has always been above halfway mark.

 

can someone please run the Carfax and/or datacard on this vehicle please?

I'd really appreciate it. It's for an 07 Caddy DTS my cousin wants to buy.

Please post here and I'll PM you or PM me directly.

Thank you for the help,