OnlyGerman

Yup, typical Mercedes not standing behind critical defects.

W205C43PFL

Sorry to hear that but is it just me or your video isn't there? Did you accidentally delisted it? Were your vehicle's VIN part of the wrist pin recall batch, if so did your dealership complete the recall yet the engine still failed?

scvillareal1

There was never a recall for this issue...I checked

W205C43PFL

There was a recall (Edit: sorry about that I meant service bulletin, I stand corrected) for the wrist pin for MY15 C-Class vehicles with the M274 as there was a factory defect. Please see the attachment.

chassis

Note to those on the thread still seeking compensation, a poster on this site enlisted a lawyer and the piston may be covered under 7yr/70k emissions warranty. Read the C-Class thread for updates.

Xbowguy

UnF@#king Believable we traded our 2012 Lexus RX350 in for this 2019 GLC300 base suv.. 2.0 turbo m274 engine build... it's not a daily driver only has 12,500 currently... but dam knowing that any given time my engine can blow.. sucks...

i'm still under warranty I didn't; opt for extended,,, never do.. sounds like things starts deteriorating after 60k. by then I should be rid of this POS and back to Lexus

DanD.

I have 18 and vin decoder shows
Engine 274920 31 395517
So like a time bomb.

dminahan

So I already got feedback that my 2021 GLC had the M264 but after this I had to work to find a vin decoder that would give me the information you referenced to verify what engine was in the GLC I just bought in May. I found the mb.vin site that broke out that engine number and then further down confirmed it was an M264 engine for my vehicle.

And what I'm hearing is they did change some things in the M264 but may be too soon to tell if it suffers from issues. I did buy the extended warranty on it however I had intended this vehicle for my daughter to carry her for over the 7 year warranty. So I"ll have to keep tabs on this I guess.

I agree it would be upsetting for something like this to happen after the warranty but with not that many miles on the vehicle. Similar but different thing happened to my husband's Volvo this fall. He needs a new engine (old one probably could have been repaired but dealer only doing new) at just over 5 yr mark and 70k miles. We fought it and apparently Volvo is covering the repair but we have been waiting for months for a new engine to make it into the US to be installed. I then had to go escalate my vehicle replacement this fall instead of waiting to make what I thought I wanted work for a price I was willing to pay. I had traded my larger vehicle in for the GLC this past May and was shopping around for my replacement. After I did that I was jerked around some on ordering and then started hitting issues with Mercedes dealers in my area wanting too much for their larger vehicles. I finally gave up and went into a BMW and still got at least a small discount. No idea if similar issues are happening on timelines of repairs on Mercedes. If it is taking as long that just adds more to the feelings on why did an engine die like this and now it is taking months to repair. We are approaching the 3 month mark of that car being out of rotation.

Hopefully they can get coverage extended to longer on those vehicles impacted. It is upsetting.

Lynda1951

Thanks!

Sugar_Mouth

I noticed the M264 does not ramp up boost as aggressively as the M274 does. This would reduce detonation and save the engine from excessive cylinder pressure.

W205C43PFL

Did you notice a drop in performance as a result? The M264 is even rated higher horsepower than the M274 (255hp M264 vs 241hp M274 I think?) so they might have changed something else to make up for a decrease in boost.

Sugar_Mouth

No. What I noticed is in the tuning. The newer GLC ramps boost up slower than my '18 for example. The newer one feels less punchy but has a much more linear delivery of power. I have always felt the low rpm, high boost tuning in my '18 is a contributor to my pre ignition.

W205C43PFL

I see

karmikan

It seems implausible that an highly experienced manufacturer such as MB could make an engine that self-destructs like this but it's starting to make some sense. They wanted offer a competitive "performance" 4 cyl engine (likely for marketing considerations) so they increased the turbo boost. Of course, this caused the knock sensors to dial back the timing and reduce power so they re-tuned the sensors to be less aggressive hence increased knock.
This is pure speculation of course but I have been in the middle of fights between engineering vs. marketing and marketing usually wins. It seems quite possible that this could be the case here. It's not what you would expect from a company that claims to be high-end but it is what it is.

If knock is really the source of the problem I was wondering if using an octane booster in these engines could circumvent the issue and head off a catastrophic failure. This would be a pretty pricey solution but a lot cheaper than a new engine. Appreciate any opinions.

converse

Same thing happened to me. I drive a 2017 GLC300 with about 50,000 miles. Bought used in October 2021, engine failed this month - same piston problem as everyone is describing. $12,000 for new engine not including labor. I have an extended warranty but it doesn't cover everything.

This is obviously a manufacturer's defect.

Xbowguy

Unbelievable and no one in MB is stepping up to help... It sickens me that my 2019 GLC 300 suv could catastrophically fail at any given moment I step in it... i'm Financially stuck with this car even if i wanted to trade there none to pick from anyways

chassis

Late model year build M274 piston cracking has been reported on this site. There has been no conclusive information posted on this site pointing to a specific range of affected engines. They appear to all be candidates for piston cracking.

W205C43PFL

Still too early to tell for the M264 engines. https://mbworld.org/forums/glc-class...st-my-car.html

Probably a one off but I hope those with M274 and M264 that haven't had an engine fail to not have to deal with issues like this and for those who did get it fixed to not have this issue recurring. Last but certainly not least, for those who are currently dealing with this issue, good luck on the repairs and I hope it gets sorted out swiftly.

Lynda1951

As a follow up to my original post, MB refused to acknowledge that this engine has a defect and my appeal was denied because even though I live several hundred miles from a dealer repair and had all my maintenance work performed by a MB certified auto repair mechanic – that wasn’t enough. FYI: as I did not have an extended warranty and truly never thought I would need one, I researched our sales agreement and learned a very valuable lesson. I bought the car from a friend’s daughter who was returning the car at the end of her lease (18K+) as she was on assignment out of the country. We went through the MB leasing agency that is based in ID (I thought strange as we are in CA). When reading all the terms of the agreement, which I know we screwed up on now, there was a term that claimed that this car came with NO WARRANTY/GUARANTEE, IMPLIED OR EXPLICIT, from either the leasing company or MANUFACTURER. I assumed, wrongly, that we had at least the remainder of the vehicles 50,000 mile warranty. NO, we did not. Never again am I buying a MB. We are getting the engine fixed – the dealer in Sacramento quoted $17,000 but our trusted MB shop mechanic is about $11K. We will repair and then start the search for a new car. I know it will be hard in this environment right now, but I no longer trust MB and have learned a valuable life lesson.

chassis

@Lynda1951 Thanks for sharing your experience, and glad you have decided to move on and repair the vehicle.

I agree that MB is not to be trusted. I further am of the view that MB puts out low quality trash and most people are unaware. The products look nice and are fancy and expensive, and they are low quality trash.

mikapen

Are you referring to the FTC-required "Used Car Buyers Guide," that discloses whether the Dealer has put their own warranty on the car? If so it would say "remainder of Manufacturers Warranty (if any)...."
It has no effect on a Manufacturer warranty.

Wishing you the best.

DanD.

I'm GLC 2018 owner and this concerns me a lot. I just checked the consumer reports and believe it or not GLC has no major engine issues reported.
I would recommend to contact consumer reports and BBB to report, maybe they can help
Also can you please post the VIN numbers?

chassis

The chart shows a red mark for 2016. It could be that the methodology used for the chart considers 2017 and 2018 as too new.

There are, however, reports on this site of 2018 model year piston cracking on C-, E-, and GLC- models with M274 2.0L four cylinder engines.

karmikan

This piston issue does seem to be real and MB are clearly ignoring it. I was hoping to keep my GLC for a long time but hate the thought that any trip could end up with a trashed engine. Looking around for options I came across forged piston kits made by Wossner, the kit includes the wrist pins. I contacted one of their major distributors who is in Hungary and they confirmed that the M274 pistons do seem to be a problem, so much so that they are currently sold out. I've asked them to contact me when more kits come in.

This will be a pretty expensive process if I go ahead ($574 + installation) but it might be a viable option unless the overall car market improves, no sign of that in the near future. Certainly it's a much better option than your engine turning into a boat anchor in an instant. Nice job MB.
Here's the contact info:

https://premiumtuning.hu/categories/...rods-1127.html

altay

Always buy extended warranties for luxury cars especially for german ones. And sell it a couple months before warranty expiration date. They are fun to drive, nicely designed but not that reliable. Made in germany ones have better built quality than made in usa ones