Yuille36

Yes, for both my 2010 C63 and my original 07 E63, but not for my current E63. But I have spent $$$$, to get my current E63 dailed in.


This was my first E63



Now I have this one. Sorry, I didn't have any pics of my C63.

Vladds

I only got my car at 46K miles and am now at 70k.
Although I believe that changing the antifreeze properly, as you did will definitely extend the life of the bolts as it did for you, this ship may have sailed for me, at my miles and age of car.
I may still do it though and add a thermostat replacement.

Yuille36

My current E63, I had the head bolts done with over abundance of caution as I listen to the hype. But knowing what I know now, after seeing the old head bolts and lifters for myself, I wouldn’t have changed them. As they were is great condition giving their age and the mileage. This was at 88k, I’m at 91k now. I posted all this on this forum. But having a good friend that is a shop foreman and AMG Master Tech, he said that from MB data most failure happen after or near 90k, but this is a very small percentage of the total number of engines that were manufactured.

AMG__POWER

thats what I heard in at 155 almost I’m hoping I’m just licky

hachiroku

no fault of yours or MB, but the 90k average is misleading...this will only account for the owners who have had their vehicles repaired at a Mercedes dealership. I had mine done around this time as to avoid any issue. beknownst to my own, the previous owner had the entire heads redone at Mercedes....since I do not have the actual service records i do not know if it was due to failure or not. lifters were done at the same time. this was done before 70k.

Yuille36

True, this data only accounts for engines repaired at the dealerships. This doesn’t account for DIYs or independent shops. But from thIs data, failures are quite low. I am no expert but, I will say this, there are far more engines out there still with original head bolts, than there are with the new head bolts. 👍🏽 If that gives you any comfort, and these engines have more then >100k Miles.

Dogtag114

Mine started to go at 95k miles or so. Caught them in time and had indy shop replace them.
Also just had Cam adjusters replaced. Hopefully good for a while now.

Unless someone want to talk me into selling so I can get my wife her new SUV.

I still have my Lotus for my fun car.

AMG__POWER

this is relieving to hear, in @154k and no signs (knock on wood) of headbolts needing replacement, car runs sweet and sound even with modifications, that being said I do change the oil religiously and change the coolant out frequently

Yuille36

The key is identifying that you, have an issue stemming from broken head bolts. And getting it addressed before it leads to more or catastrophic engine damage.

if you have no coolant lose, no CEL indicators, no misfires, no white exhaust smoke then your fine, but the minute you detect any of these issues, shut the car off immediately and get it flat bedded to a shop for diagnosis and repair. Other than that you should be fine. And remember that this phenomena didn’t effect every M156 engine out there, only a very small percentage 1-3%.

I personally mitigated this issue by changing the engine coolant every 2 years, as head bolts are exposed to engine coolant their entire life. And having fresh engine coolant helps mitigate the corrosion on these bolts. It’s a common sense approach. Besides engine coolant is cheap, head bolt replacement is not.

I’m not advocating that someone follow my approach, but I’ve never had any issues with any of the three M156 equipped AMGs I’ve owned.

I certainly understand someone wishing to change out their old head bolts, just for peace of mind. But I will say this, I did fall to the hype, and regret having them done. Granted I have peace of mind now, but there was nothing wrong with my old head bolts or lifters that would justify replacing them. Hindsight is 20/20 🤔. Now that there done, I never have to worry about this issue again. 👍🏽

AMG__POWER

thanks for this great info! I don’t have coolant loss, or white smoke from the catless LTH, but I do have a CEL for code p2198, 02 sensor signal stuck, I assume this is from the LTH though. Car runs great, no misfires etc
I figured there’s no way every single m156 is affected by the headbolts issue like stated here but hey, I do understand people wanted to be precautious
do you reccomend I change my coolant if I did a flush 11k mikes or 18 months ago?

Jasonoff

Swapping the bolts out one at a time is just cheap insurance. You DO NOT want coolant circulating through bearings. No matter how much you flush, they will never be the same.

AMG__POWER

I get you, did you have aftermarket stuff or oem? I just feel like if I’m not having symptoms maybe I can wait?

Yuille36

Engine coolant contains anti rust inhibitors in the liquid. Introducing newer coolant with better rust fighting properties will help mitigate the corrosion buildup on the bolts. This is simply logic. This will in no way prevent the head bolt from cracking, it’s only a mitigation factor. But this can prolong your existing head bolts. One can agree or disagree with me. Your choice, but I choose to change my coolant every two years regardless of mileage. And if you ask any MB tech, they will tell you that changing your coolant wouldn’t hurt, plus it cheap insurance.

Jasonoff

Unless you're running a blower at high boost, aftermarket components are irrelevant.

Once you have symptoms, the head gasket is already compromised and the heads need to come off so they can be replaced. That's when the job becomes exponentially more involved.

The whole point of replacing them one at a time preemptively is to maintain HG integrity and never have the problem.

AMG__POWER

cool! That’s for the info again, which coolant do you use? I’ll change it out soon

AMG__POWER

I thought it starts with low coolant which is when you should change ASAP before bad damage

Yuille36

I had my head bolts replaced one by one, in order to maintain the clamping force on the heads. Also low coolant isn’t indicative of bad head bolts. This could be a symptom of a crack radiator, coolant hose or a leaking water pump.

AMG__POWER

what would you say are the main tell tell symptoms of it then? Bc as of right now the car runs excellent with no issues besides the o2 sensor from the headers and the tpms. I would prefer not to rip it apart for no reason if there’s nothing wrong

Yuille36

If you have no coolant lose, no CEL indicators, no misfires, no white exhaust smoke then your fine.
Since you have no issues, and your past >150k, I wouldn’t worry about it much. I think that your past that point, I would just change your engine coolant every 2 years, and you should be OK.

AMG__POWER

thank you for all your help, is the o2 sensor on 63 normal with LTH on my e55 with headers it is

Venom63

199k miles over here

AMG__POWER

holy cow! Stock headbolts?? Any mods

Venom63

Stock head-bolts. Engine wise, it’s stock besides the straight pipe exhaust. For a long time it had a tune and a flamethrower kit though.

AMG__POWER

that’s crazy! What year

Venom63

2008