mikapen

Dunno about that source. I think there was ONE reported piston cracking reported. At first they thought they had a V6, and then changed to a four. Then further investigation revealed driving for weeks with the oil light on. You decide.
The new four in the V167 GLE350 sure propels the car with more authority (and +5 mpg) compared to the old V6 in the W166. The pistons were changed because new materials provide slicker surfaces and lower internal friction, as I understand it.

I do agree about the variable reliability of CarFax. It really depends on how much time and detail the repair facility puts into the CarFax report, it they even bother. I checked a 2003 C Class I traded, years after it was gone, and CarFax had no record of my $12,000 front crash repair. It didn't set off airbags so, I think, it wasn't "required."

chassis

@mikapen Please do your homework and read the GLC, E, and C class fora. You will find for your reading enjoyment multiple reports of piston cracking on the M274 2.0L 4 cylinder turbo on which the M264 2.0L 4 cylinder turbo is based, and is used in the V167, W213, W205 and X253. It will be interesting to see owner reports when the M264 starts to exceed 50k miles.

This just in, a new report from today on a W205 with 32,000 miles and cracked #1 piston. https://mbworld.org/forums/c-class-w...-miles-15.html

mikapen

So, again, different engine.

mikapen

Doing a little homework here
The M264 engine is NOT based on the M274. The M264 is part of the new modular family, where each cylinder is 500cc, and they are built in I4 cyl 2 liter, I6 cyl 3 liter, and V8 cylinder 4.0 liter. I don't think much is shared at all. At least that's the way I read it. https://media.daimler.com/marsMediaS...l?oid=14315460

chassis

@mikapen Spend some time with EPC and you will find a substantial number of major components (crankshaft, connecting rods, crank bearings, and more) common between M274 with cracked pistons and the M264 in the V167 and other vehicles. Pistons have been changed in the M264 so the jury is out whether the piston cracking problem has been solved. It is a similar scenario to the camshaft position sensor leaking on earlier engines, and MB made many design changes on the sensor until they seem to have gotten it right.


M274 was 0.5L displacement per cylinder before the inline 6 and M264 started production. That’s not novel. The M276 3.0TT is 0.5L per cylinder and it’s not from the same family as the inline 6. Cylinder displacement alone does not put engines in the same family.

The M272 and M276 3.5 both had the same displacement per cylinder and were totally unlike each other. M272 was 90 degree vee with balancer and the M276 had none of that, being a 60 degree with no balancer.

The M264 4 cylinder has an asterisk on it until many owners have passed the 100k mile mark without the engine grenading like the M274. 100k miles is nothing for most manufacturers but it is a Herculean feat for MB.

mikapen

You need to do more research. The "same displacement per cylinder" does not make it that same engine. Otherwise we could be talking about BSA motorcycles in the same sentence. Bore/stroke, cylinder spacing, coolant passages, piston/ring materials, cylinder lining, block alloys, crank angles, pin placement - the list is enormous. They are not even close as engine designs.
Your reliance on Forum posts as indicators of reliability is what needs to improve.
Name a common internal part of both engines you are comparing with your hearsay stories.
We'll all thank you

chassis

Thanks as always @mikapen We agree that displacement per cylinder does not link engines into a design family. It’s good to share that common ground together.

Regarding the question posed, one of many parts shared between the piston cracking M274 and the newer M264, which is based on the piston cracking M274, is: crankshaft. There are more parts shared between the engines than the crankshaft.

mikapen

You could be right. I had been looking at the evolution of the 2.1 diesel, which is a wholesale departure from its previous configuration. Crank offset, piston pin placement, etc.

So the crank on the old M274 was hollow, like the M264? I know the pistons are specifically claimed to be different.
How do you find that information?

chassis

mbparts.mbusa.com

And other sites. mbepc.net is another

mikapen

Thanks for those sites. As I suspected, you are incorrect about those two engines sharing the crankshaft, or several other internal parts I checked.
As I said, and the info from Daimler I posted reinforces - the engines are not related.

Conclusion - your continuing posts that are condemning just about everything on new Mercedes cars / engines / MBUX / interior are simple BS.

Sometimes you make a useful post, but most of the time they are just trolling, and usually just wrong.
Keep up the useful posts, but please quit thinking that one post about a defect on a ten year old car represents the real world. This is an internet forum. It's certainly not statistically significant.

I suggest that others on this thread take chassis posts with a few hundred grains of salt - they are opinions without substance.