Cylinder cylinder wall scuffing with pictures...oil additive might help?
And we're not even talking about Ethanol issues either
I believe testing of gas after a catastrophic engine failure might reveal some interesting results....I think the key takeaway here should be don't get caught up in pictures, but rather rely on a proper leak down test for analysis. I think it's also unrealistic to expect an engine that is run hard, puts out those kind of HP numbers, coupled with hot tunes, relatively high compression (10:1) and north American gas blends to live for 100,000+ miles.
That would be a stretch for coated aluminum cylinder walls living with high cylinder pressures.




The point I'm making is it's a candle, the hotter you burn the wick the quicker you're going to run out of wax.
Plenty of M157/M278's are making it past 100k, but they probably aren't being raced or beaten hard and are pretty well maintained.
But also, were extracting a lot of power and efficiency from these engines. I doubt they are going to be in the same league as say, an M120.
Also a lot less margin for error, things such as the oil wicking issues of the cam sensors can create catastrophic chain reactions....
Last edited by crconsulting; Dec 20, 2022 at 09:56 PM.
Its fast enough and living where i do there arent any open areas to drive that fast anyways.... its my daily and i need to make surei t stays that way
I have a Mercedes m157 engine (5.5liter bi-turbo) in my short commute, daily driven ride. I bought the car with 50k miles with fresh dealer oil. at 55k i changed the oil and put a cheapo boroscope into cyl 5 (known to be the first cylinder to show wear)
and as you can see there is some minor scuffing.(1st image at 50k, 2nd image at 55k) At 55k (1 year later) I did a 2nd oil change. again I did the boroscope and got the 2nd image with notably more piston scuff. I was running Liqui Molly 5w40 leichtlauf. I also ran a mild tune for 4k of the 5k miles. I've now pulled the tune and am sending a sample to blackstone. I'm not looking for magic but if an additive could slow down the rate of damage I'd like to try. I'm interested in the Liqui-moly Ceratec or MoS2. I'm in a colder climate (ny state) and have read that some suspect (mostly porsche owners that seem to be having a cylinder scoring problem) that when cold, the piston warms and expands faster than the aluminum cylinder and can cause this. I've also found more general piston/cylinder info suggesting this is a lubrication issue. I'd welcome any thoughts...Thanks for reading!
When you bend a rod thats when scoring starts usually and it will be evident in your oil changes. You will start finding small metallic pieces in the oil, check the bottom of the container after an oil change. Also take the oil filter and look thru it.
I had a slightly bent rod in my bone stock E63S, thats how i know. But i use to drive it like its stolen, literally. Frequent launches and high speed pulls regardless of the ambient temps. Never had a misfire or a check light, oil changes every 1500-2500 miles, 5w40 +1 ceratec. No oil consumption, ever. I later tuned it anyways and was still fine for another 5k miles, Eurochaged stage 1. Then bought a lower mileage 2015.
Meanwhile my friends S63TU was toast with mild to hard driving. It was consuming like 2 qts every 500 miles. LOL Less than 20k miles on the odo, only a muffler delete.
I strongly believe M157 would be a very solid Stage 2 car with upgraded connecting rods alone + proper maintenance, according to climate and driving style.
The Best of Mercedes & AMG
Also heres a photo for reference of the shavings i was finding. Some were magnetic, most not.
. Not sure if it was worth risking potential engine destruction but someone had to show this guy what a wagon can do!
. Not sure if it was worth risking potential engine destruction but someone had to show this guy what a wagon can do!One pull is nothing from a roll, you want to avoid pushing it when heat soaked and back to back pulls. Rewire your intercooler pump to stay always on, that will be very beneficial for IATs. Theres a thread showing how if you haven't already done it.
I have a Mercedes m157 engine (5.5liter bi-turbo) in my short commute, daily driven ride. I bought the car with 50k miles with fresh dealer oil. at 55k i changed the oil and put a cheapo boroscope into cyl 5 (known to be the first cylinder to show wear)
and as you can see there is some minor scuffing.(1st image at 50k, 2nd image at 55k) At 55k (1 year later) I did a 2nd oil change. again I did the boroscope and got the 2nd image with notably more piston scuff. I was running Liqui Molly 5w40 leichtlauf. I also ran a mild tune for 4k of the 5k miles. I've now pulled the tune and am sending a sample to blackstone. I'm not looking for magic but if an additive could slow down the rate of damage I'd like to try. I'm interested in the Liqui-moly Ceratec or MoS2. I'm in a colder climate (ny state) and have read that some suspect (mostly porsche owners that seem to be having a cylinder scoring problem) that when cold, the piston warms and expands faster than the aluminum cylinder and can cause this. I've also found more general piston/cylinder info suggesting this is a lubrication issue. I'd welcome any thoughts...Thanks for reading!
If any of you are Porsche owners and on any of the Porsche forums, you'll find countless posts about this topic. I've devoted years to researching this topic and developing solutions for Porsche engines with cylinder bore scoring. That said, there are many contributing factors - changes to manufacturing methods as well as lubricant and fuel quality all have an effect on cylinder bore scoring. Vehicles driven in colder climates also seem to be more likely to suffer from this issue as mentioned by the OP.
That said, many of the things we do to help prevent bore scoring in Porsche engines would directly apply to any Mercedes with an Alusil engine block:
https://lnengineering.com/products/w...e-scoring.html
Understanding the wear mechanism for engines with alusil blocks is the first step. These engines need an oil with high levels of moly friction modifiers. ZDDP can help for sure, but it can't bind to the aluminum and silicon particles that make up the Alusil cylinder walls, but moly can.
Adding Ceratec would help - this basically boosts the moly levels in the oil, however the use of thinner oils reduces the HTHS viscosity of the oil which is good for fuel economy but bad for protecting the engine. The problem we have with Porsche engines is that the factory approved A40 and C40 oils have little to no moly. You have to in essence look to the aftermarket to find a better oil for these engines. That's why we recommend Driven DT40 or DI40 to our Porsche customers. I've used Driven DI40 oil (for engines with direct fuel injection) in my S550 for years since they have very high levels of moly - the used oil analysis comes back perfect every time.
What you want to look for is increased silicon, aluminum, and iron levels in the oil - this will be the first signs of bore scoring, even before you have piston noise or increased oil consumption:
Used Oil Analysis results from an engine with cylinder bore scoring
I highly believe that shorter oil change intervals and better oils (ignoring manufacturer recommendations and not using a spec oil) is the first and easiest thing you can do to prevent this issue.
In the case of the early scoring reported by the OP, I'd recommend going to a slightly thicker oil that is formulated with increased ZDDP and moly. Normally, this would mean going from a 0w30 or 5w30 to a 5w40 or if running a 0w40 or 5w40, switching to a 5w50. The added viscosity will provide extra "cushion", but there is nothing that can reverse the cylinder bore scoring. We've had customers extend the life of their Porsche engine for years as long as it's caught early and they switched to Driven's oils.




Above is my recent Blackstone oil report from about 300 miles ago. This engine currently has 31k, a eurocharged s2 pump gas tune since 19k. I have been using liquid moly 5w40 since 15k and use ceratec every 3rd oil change. This is also on 3,000 mile oil changes (which many dispute is a waste and way to soon), but I am fine with it as my car see's about 5-7k miles per year. You can clearly see high levels of molybdenum in the oil from using the certac on the last oil change prior to this one.
Last edited by Mojo20032004; Oct 17, 2023 at 10:47 AM.
Above is my recent Blackstone oil report from about 300 miles ago. This engine currently has 31k, a eurocharged s2 pump gas tune. I have been using liquid moly 5w40 since 15k and use ceratec every 3rd oil change. This is also on 3,000 mile oil changes (which many dispute is a waste and way to soon), but I am fine with it as my car see's about 5-7k miles per year. You can clearly see high levels of molybdenum in the oil from using the certac on the last oil change prior to this one.
had the mechanic get to inspect the cylinders and he said that
Cylinder 1 had extreme scoring and
Cylinder 2 had some scoring plz find the attachments
Car has 57k miles
Car now has weistec stage 1 tune and car had always had Renntech stage 1 I think since its bought from the dealer
always used Chevron 91octane
Thanks In Advance..
Last edited by Gouth; Oct 17, 2023 at 12:14 PM.







