2014 Mercedes ML350 Bluetec OM642

[johnand]

This is my first analysis on my recently purchased 2014 Mercedes ML350 Bluetec. A little disappointing Iron number considering the low mileage and short drain interval and 90% highway driving. Silicon is possibly a culprit as I found one of the air filter seals was torn. It has been replaced and will continue to test. Sticking to 5K change at this point. Sticking to 229.52 spec oils for now, as it is a CPO, so I am still under warranty. Would love to try the Mobil 1 X3 0W-40, but it is a little hard to find. It is the only 40W under the 229.52 approval.

 

[FlyNavyP3]

Silicon isn't as high as I would expect to cause an increase in iron wear, perhaps this engine just sheds more iron. All looks healthy enough not to worry.

 

[Gubkin]

Liqui Moly Top Tec 4600 5W-30 (SN, C3, 229.52, dexos2) ?

 

[Gubkin]

Should be better 10w-30/40 CK-4

 

[johnand]

Originally Posted by Gubkin
Liqui Moly Top Tec 4600 5W-30 (SN, C3, 229.52, dexos2) ?


Yes, it has the same SN, C3, 22.52, and dexox2 specs, but is the 4605, not 4600. https://products.liqui-moly.us/oils/top-tec-4605-sae-5w-30-1.html

Can't really find anything specific on the differences between the 4600 and 4605. 4605 just seems more readily available where I am.

 

[johnand]

Originally Posted by Gubkin
Should be better 10w-30/40 CK-4


Agreed. And I plan to move to one after remainder of CPO warranty is up. Any recommendations on one you like?

 

[maintenanceMan]

I've got close to 200k on an om642 now. I usually run heavy duty diesel oils. I don't trust the Mercedes specs to be all about longevity of the engine, maybe more about getting emissions through the warranty period.

 

[Pelican]

What's the weight recommended in the manual? I don't think it's a 5W30, but my memory may fail.

 

[Audios]

Interesting to compare, Im expecting a report for 6k on Fuchs 5/40 soon, so it will be nice to see how it compares.

 

[spk2000]

How is the fuel mileage in that bluetec engine?

 

[johnand]

Originally Posted by Pelican
What's the weight recommended in the manual? I don't think it's a 5W30, but my memory may fail.


0W-30, 5w-30, and 1 lonely 0W-40 is approved (Mobil 1 X3 0W-40) for MB 229.52 spec: https://bevo.mercedes-benz.com/bevo...e_id=1&blatt=229.52&suchbegriff=

 

[johnand]

Originally Posted by spk2000
How is the fuel mileage in that bluetec engine?


In the 8K miles I have owned it my lifetime average is 27.1MPG. This is 80% highway. On my daily commute I occasionally hit just over 30MPG.

 

[johnand]

Originally Posted by maintenanceMan
I've got close to 200k on an om642 now. I usually run heavy duty diesel oils. I don't trust the Mercedes specs to be all about longevity of the engine, maybe more about getting emissions through the warranty period.


I agree, MB spec is geared towards life of the emissions equipment while sacrificing the engine life. Any particular HD diesel oil you recommend?

 

[johnand]

Originally Posted by Audios
Interesting to compare, Im expecting a report for 6k on Fuchs 5/40 soon, so it will be nice to see how it compares.


Yes, I am interested to compare as well. I'll keep a lookout for your post.

 

[maintenanceMan]

I think most of the big name HD diesel oils are robust. Names like Valvoline, Mobil, Shell. I typically use Rotella 5w40 in the winter and Mobil 15w40 the rest of the time. The mobil I got in a screaming deal awhile back, found the deal here. I usually run about 5,000 mile OCI. I don't have a dpf and have a Green diesel tune for most of the life of it. I believe EGR is shut off. My oil stays clean and clear until about 3,000 miles.

 

[maintenanceMan]

Also I use the ox380d Mahle from rockauto and a fumoto valve.

 

[SZR48207]

I was just reading about this car and this engine and fuel dilution is a concern if you don't let the DPF regen happen correctly. If you can't hit regen then the engine will still dump a lot of excess diesel into the cylinders and it'll seep past the rings and get into the sump.

You said you mostly drove highway so you should be fine but are your trips under 15 minutes?

I'd like to get a CPO MB diesel myself someday but it seems like the emissions system does NOT favor short trips.

Link to article I read: http://www.stephensservice.com/bluetec-diesel-issuesproblems/

 

[Bjornviken]

Try an other oil

 

[Audios]

Great fuel economy! My GL is averaging 19 over the 6300 miles ive had, however our commutes are pretty short, mine is about 5 miles each way and hers is about 12. I guess it is a bit bigger than the ML as well. I do have a green diesel tune as well, but I am worried about switching away from the Low SAPS oil and causing issues down the road. Otherwise Id switch to the 5/40 TDT or maybe a rotella T6. I guess the analysis will give me a better idea of whats going on.

 

[maintenanceMan]

The only real option is to get rid of the dpf/regen. To my knowledge, this is only possible on pre adblue om642, like mine. The dpf is incredibly restrictive, you can feel the difference in the engine braking once its been removed. Picked up about 3 mpg with tune and dpf removal. Durability is sure to improve as well.