Are the contemporary 2.1 diesel engines dependable?

[Martin_Smith76]

Greetings,
I have operated E class Estates since 1984. S123, S124, S210, S211, and S212. I consistently opted for larger Diesel engines, including the 3-liter straight-six and, more recently, the V6.
I am currently seeking a replacement, preferably an 18 or 19 plate, and I have discovered that my engine options differ, as the E350 is equipped with a 2.1 unit. I lack familiarity with these engines and need insights into their reliability and any peculiarities they may possess.

Given that this may be my final vehicle, I intend to select judiciously. I seek to learn about the experiences of current users, both positive and negative. Thank you.

[MercedesMan98]

The e350d is now an inline 6-cylinder engine, rather than a V6. My father recently acquired a pre-owned GLE350d (utilising the same engine), so I thoroughly examined the known concerns. The primary concern with this engine (OM656) is the potential failure of the coolant and brake vacuum pumps. The pump seals begin to deteriorate, initially resulting in diminished brake performance, subsequently causing oil contamination in the brake-vacuum system and coolant leakage into the engine oil system, ultimately leading to sludging. The most problematic aspect is that the pump is located deep within the engine, necessitating engine removal and cylinder head disassembly. Furthermore, Mercedes-Benz is unresponsive once the three-year guarantee has lapsed, unless one possesses a Mercedes-Benz used warranty. Conversely, a vehicle from the 2018-19 model year would likely have already experienced the issue, and Mercedes-Benz issued a Technical Service Bulletin (TSB) software update to convert one of the pump valves to a unidirectional function to avoid coolant ingress. To do a basic inspection, identify the brake vacuum servo, detach the vacuum pipe and insert a pipe cleaner. If any oil is detected, it is advisable to discontinue further investigation. No significant known issues exist regarding the OM656.


The OM656 is fundamentally the 2L OM654 with two additional cylinders attached; it appears to be a superior engine compared to the OM654, which has had cam rocker arm wear. The reliability of the AdBlue system has improved due to its components being positioned closer to the engine block, leading to a quicker warm-up.

[allcarsnew007]

Based on my observations over the years, it would likely be more advantageous to opt for an older Mercedes Benz, particularly when considering the newer diesel models.

[sighn34]

What is the mileage requirement for the diesel, my friend?
I normally advise against contemporary diesel vehicles equipped with AdBlue.

[Martin_Smith76]

Thank you. My mileage has significantly decreased since my retirement, making petrol my most viable option; nonetheless, I am encountering considerable scarcity. My preference for diesel is primarily a matter of habit. Indeed, Adblue intimidates me. The most recent models I can locate are from 2016 and 2017, nevertheless they predominantly possess higher mileage than my 2012 vehicle. S212 with 265 horsepower. Thank you

[sighn34]

Audi and BMW produce numerous gasoline-powered vehicles.

[veroguittar]

It is preferable to deal with a familiar adversary.

[SteveRulz23]

[Gorrillaas]

Are you seeking an E class?

Recent C-class petrol vehicles, as well as hybrid A250e hatchbacks and saloons, are available in substantial quantities.