..........If your car is a 2014 production year or newer and is using M276.9 ( 3.5 NA ) or M276.8 ( 3.0 or 3.5 Turbo ) or M278


I have not visited the new Bevo much, now no more Bevo.

https://bevo.mercedes-benz.com/index.php?language_id=1

===========

Mercedes-Benz Operating Fluids

Due to the spin-off from Daimler Truck AG and the renaming of Daimler AG in Mercedes-Benz Group AG,
we decided to no longer develop the BeVo website. Starting on 12/01/2021 the content will be published on 2 separate websites.
===========

This is what I mean by misleading information.
If you go to here : https://operatingfluids.mercedes-ben...tegory/coolant
You can and should go to both the #1 Sheet 310.1 and #2 Sheet 320.1 to know the suitability of the coolant you need.

In #1 Sheet 310.1 , this is what you get ( based on 25th Aug 2023 website appearance ) :
https://operatingfluids.mercedes-benz.com/sheet/310.1

Simple explanation : 325.0 = Concentrated 100% coolant and the 326.0 = Pre-Mixed 50/50 coolant and proper distilled water
If you land only on #1 Sheet 310.1 and do not proceed to #2 Sheet 320.1 , you will get screwed reading what I red mark below as bullshi-et



Now, be careful with definition of PRODUCED AFTER XXX YEAR.
Year of production is not the same as Model Year.
My car is a year 2014 model year and sold in mid 2014, but production date as per Data Card is a bit sooner than 30th Aug 2013


Being a locally assembled car in Indonesia, surely it takes time for shipping from germany and actual local assembly.
I do not know about USA MBs, are they locally assembled in USA or how ?


Anyhow, if one do not visit #2 Sheet 320.1 to know the ACTUAL suitability of the coolant type you need , and your car is say an E400 of Model Year 2015, you may end up using the wrong coolant as per #1 Sheet 310.1
and that can be bad for your engine cooling system

See #2 Sheet 320.1 : https://operatingfluids.mercedes-benz.com/sheet/320.1

This is what we will get :


So, if you bought W212 E350, E400 and E500 of Model Year 2015 and up to 2016, if you do not read properly to this page ( #2 Sheet 320.1 ), you get screwed thinking blue coolant 325.0 and 326.0 is
not allowed as per #1 Sheet 310.1

Below information is not too bad , at least the word CERTAIN VEHICLES is mentioned.
Restriction: For all vehicles up to and including April 2014; Important: Service measures for certain vehicles that required a conversion from 325.0, 326.0 to 325.6, 326.6 must be observed.




Hope this will help newbie buyer of pre-owned MB of model year 2015 and 2016 with the mentioned engines M276.9 , M276.8 and M278.
If for non USA MBs, say Europe or Asia any E200 or E250 with M271 engine of model year 2015 and 2016 will also get screwed from #1 Sheet 310.1 misinformation.

When was M276.9 ( 3.5NA ) and M278 were introduced in W212 ?
Wiki said for M276.9 ( 3.5NA ) was as early as 2012 and M278 as early as 2011.

Stick to blue color coolant 325.0 or 326.0 , which I believe strongly is is better/more suitable formulation for our older engine metals and seals materials.
When it comes to chemical compatibility, newer is not always better. Blue color coolant 325.0 or 326.0 has a very long proven track record.


Have fun shopping for your pre-owned W212.

 

These are the engine variants of M276.8 and M276.9 and M278
DE = Direct Injection
LA - Turbocharged aftercooled
M271 if EVO, that is Turbocharged aftercooled
30 = 3,000cc or 3.0 Liter
35 = 3,500 cc or 3.5 Liter
40 = 4.0 Liter
46 = 4.6 Liter
OM = Diesel engine




Wow, so there is a Direct Injection version of M272.....

 

For the E-Class W211

 

Appreciate you sharing with us your discovery and information on this.

 

Me never know anything about W211 era engines.
So did W212 ever get DI / CGI version of M272 ?
Thanks my man.....

 

Here is a photo of a W212 with a M272 CGI engine. Notice the CGI badge on the right-side tail lamp. It was apparently sold on non-USA market. There is also an application of this engine on a CLS 350 CGI. If you search for "350 CGI" Blue Efficiency, you will find a few articles.

 

CGI = Charged Gasoline Injection MB speak for Direct Injection gasoline

FSI = FSI stands for”Fuel Stratified Injection,” TSI for “Turbo Stratified Injection.” Both of these initialisms apply to engines with Volkswagen Audi Group's direct fuel injection technology.

BMW = not any code I know of

Toyota = D4 - Direct injection only
Toyota = D4-S Direct Injection and Port Injection combo
Toyota vehicle that has both direct fuel injection and port fuel injection. You will see port fuel injectors in the intake manifold and a direct injection fuel pump. Toyota calls this system the D-4S or Dynamic Force Engine (the “S” stands for superior) and the earliest application was on the Lexus GS SUV with the V8. The D-4S system is not a “cold start” or “dousing” injector system, like that on V6 engines from the early to late 2000s.

Mazda = Skyactiv-G Direct Injection and crazy high compression 14:1 ( non turbo )

Everyone uses unique term

 

Switch to Propylene Glycol and all those questions and bs problems go away. Its supposed to last longer as well.
I too was reading up on what coolant goes with what year, and also found mistakes and contradictions. So rather than buy the wrong thing, flush it and swap in propylene. I've used it in all my other cars with no isses. I'm unaware of any drawbacks, but if anyone knows of any, please share. I buy Sierra brand fyi.

 

Since you talked about Mazda, what about Skyactiv-X what is that about?

 

Thanks for sharing your experience.

 

I have a story to tell about glycol, be it the less toxic propylene one or the ethylene one we use for cars.
For car use I stick to what OE recommends or enforce, sweet and simple.

I took more learning between these 2 glycols when I was tasked to replace the "coolant" used on a water chilled marine air-cond on a yacht.
Basically water chilled type aircond cools down the "coolant" to +2C ( 35.6F) and send it out to all indoor units in each rooms. Since this is water based and not refrigerant based, we can not call the
indoor unit as evaporator, we can call it cooling coil only. There is no liquid to gas change of state involved as far as the indoor cooling coil is concerned.
The actual compressor still uses refrigerant to chill the coolant via heat exchanger...yes, but the refrigerant stay in the engine room where this HVAC main system is located.

Here is a good read : https://www.superradiatorcoils.com/b...h-should-i-use
For tropical country use on cars, I will not use propylene glycol due to its poorer heat transfer properties and "heavier" work on the water pump due to its higher viscosity.
However the main concern when dealing with these two types of glycol is actually the fact that unless we get an inhibited type, these 2 types of glycol actually promote corrosion.
Yes, corrosion. The glycols will produce organic acids as they degrade you see. This is a good read : https://www.nchasia.com/images/did_y...Guidelines.pdf

So when you buy say the MB 325.0 or 326.0 coolant, it has rust inhibitor added to it, which MB will choose according to the types of metals used in that particular engine and also compatibility with the
seal materials. MB buy these coolant from BASF, it is called G48 Glysantin : https://www.glysantin.de/sites/defau...tt_g48_eng.pdf

And how can MB recommend such a long life for this coolant ?
Well, in the oval-round coolant reservoir/expansion tank, MB added a pouch of chemical inside it to slowly disperse additional inhibitor in order to keep the coolant "healthy" and not corrosive.
Audi/VW group does that too and so many other cars claiming coolant life exceeding 5 years.


From one of VW's Self Study Program 514 page 31:

Coolant Expansion Tank with Silicate Repository

The coolant expansion tank contains a silicate repository. Silicate is used to protect the aluminum components in the coolant
system from corrosion. There are silicates in the G13 coolant, but they are used up over time if the engine is subject to high
thermal loads.

To compensate for the silicate consumption, silicate is taken from the repository and added to the coolant. The silicate
repository provides additional protection against corrosion for the aluminum components in the coolant system over the entire
lifespan of the engine.

==========================
OE of VW group coolant

GLYSANTIN® G48®-->VW G11
GLYSANTIN® G30®-->VW G12+
GLYSANTIN® G40®-->VW G12++
GLYSANTIN® GG40®-->VW G13
GLYSANTIN® G65® --> VW G12evo

==============================


MB 325.0 coolant



So what is this WEIGHT GAIN below in green ?
That is the thin film like coating the rush inhibitor becomes, to prevent the rust or oxidization on the aluminum alloy.




During my older days doing yacht maintenance, and since I am in the tropics with no winter and no risk of freezing, and older marine diesel operating temperature was a cool 85C unlike our Mercedes 95C+ coolant temperature,
we only use distilled water and add 5% of the recommended corrosion inhibitor from MAN Diesel or Caterpillar Diesel. There is no better heat transfer fluid easily available compared to water ...PERIOD.

So , when thinking coolant, do not only think of its heat transfer properties, think of how its rust inhibitors will work best for your engine.
For countries with winter, surely its mix ratio to the distilled water is to be observed for prevention of freezing and engine block bye bye.

 

What about waterless coolant?

Evans Waterless Coolant, Prevent Engine Overheating (evanscoolant.com)

 

Interesting about the secret pouch of chemicals. I don't suppose you can buy that?
Thanks for the info and links S-Prihadi!

I'd imagine the Evans stuff is just undiluted, and too thick? I remember a hotrod mag did a story on 100% glycol. It didn't work out so well. I won't even use the normal 50% coolant mix because I want it thinner, to cool better, so I use ~25%. Basically every car I've owned would get hot at idle in the summer, and I learned pure water helps. So I only run the 25%, or less, to lube the pump and prevent corrosion, any more seems like a waste to me.
My Benz still has the oem coolant in it, 2016 made mid '15, which is why I was looking into coolant. It's oem summer idle temp was stupid hot, like 230F. So I made some ecu changes and now it"s ~200. Still hotter than I'd like, but the water pump has trouble flowing enough at idle. If I bring it to ~800rpm it'll drop to 195. The thinner coolant mix will help, but we'll see how much if ever get around to it. Might even try Water Wetter, which I've used a couple times in the past but I can't say I noticed a difference.

 

Too bad that chemical pouch is not for sale separately, you need to buy the oval black-white coolant bottle, which is a need per 10 years too because the chemical would be
depleted by then, and also this plastic tank will eventually crack. I already replaced mine last year, that is year 8th of the car.

You are correct to say that the water pump at idle is rather slow for cooling purpose on a hot engine, raise to 1,500 RPM if your engine gets too hot is a faster way.
However, you need to know these :

01. If you rely on MB coolant gauge at the instrument cluster, that is programmed on purpose to be a white-liar.
Read here : https://mbworld.org/forums/e-class-w...inda-liar.html
So when you speak of coolant temperature, you must use OBD gauge or scanner , which is the most accurate one as per ECM data output.

02. Our thermostat has a heater called R48, hence there is a wire into the thermostat and that is not coolant temperature sensor, that is heater power wires.
This heater is to speed up the opening of the mechanical thermostat, which still uses conventional wax-to-melt.
However, the sad news is, our thermostat due to its design to work with that R48 heater, the wax inside the thermostat is no more the traditional 86C/187F melting point,
but MB uses ( like BMW ) a higher melting point one at approx 102C/215.6F.
So when this heater has weaken and can't produce enough heat to melt the wax, your coolant temperature will be no more cooler than 102C + 3C at least = 105C or 221F.
3C I added is the "loss". Wait, there is more surprise......


M278 Thermostat Assy, with heater




03. The thermostat is one thing and without a proper radiator fan speed cooling the coolant, even opening the thermostat 100% or even removing the thermostat is of no use
when car is stationary. The speed of the radiator fan is commanded by the ECM, and it has its own algorithm. Sometime you can "beg" a bit more cooling fan speed by
turning your HVAC to maximum blower speed and coldness, because this cooling fan is shared one with HVAC system and there is some fan speed allocation provided for HVAC.
You can see how many % is given to engine and how many % is given to HVAC under ECM N3/10 live data.

Here is the heater R48 in action when only coolant has reached 90C.
Coolant temp values are via OBD, so it is the accurate one.

At 89C/192F heater is still not heating up.







At 90C, the heater is starting to be powered up a tiny bit, 18% duty cycle only. This is a PWM type of power.







At 95C / 203F the ECM is still only pushing partial power to heater, not even 40% constant duty cycle.






ALL ABOVE 4 IMAGES ARE BASED ON A STATIONARY TEST


=========================



The dynamics of the heater and target coolant temperature is rather complex when car is moving and under load.

I give you some examples :
Upon engine starting from COLD, the ECM will set up a target temperature of 105C/221F. BELOW IS ENGINE OFF AND COLD







Also you need to be careful when using any scanner or Xentry when you look at the R48 Heater percentage. That % is opposite value, 100% means 100% OFF , yep sound crazy. See item 2 in red.






This is what R48 82% means. 82% OFF or 18% power is to the heater R48 hahahahah
Now look at item 1, the coolant target temperature has change to 90C / 194F and no more 105C / 221F like when engine is still COLD at first engine start of the day.






You see, 105C/221F coolant temperature is actually the most thermally efficient temperature for combustion. So once in a while, MB designer thru its ECM algorithm will push coolant temperature to 105/221F and even 110C/230F when
there is a "safe" opportunity. What is a "safe" opportunity ? Among others is when ambient temperature is cooler than or at 22C / 71.6F , or when it is raining and radiator get extra cooling power from rain water + wind velocity of the moving car.

Above is the coldest ambient temperature my car has even been at...LOL. I am at a mountain, hence you see 20.9C. Otherwise 32C is my daily temperature in Jakarta city.








======================


So you must first understand how the thermal management is done on our car. You ECM is also MED177, same as mine. Very likely our thermal algorithm is identical if not 100% the same.

There is one parameter which ECM can not control.
Wind speed of a moving car, which is better than the 800watts radiator/HVAC fan on the car for cooling the coolant, when car velocity is 62MPH / 100KM-H or faster.

We too can not control how the ECM will do when and what for its thermal management.
The wear and tear item will be the heater and the thermostat.
AA. If the heater is weak, it may not be able to heat up the wax thermostat fast enough as ECM would like and there will be the delay or a bit elevated coolant temperature before actual
coolant temperature target achieved.

BB. If the thermostat wax leak out, usually too cold a coolant temperature is the result. However I have seen damaged thermostat push rod as such the opening becomes not 100% when
it should be a 100%, hence coolant temperature then rise above target.

For my M276 3.0 Turbo, which shares the same radiator as your M278, same body aerodynamics for our W212, the best cooling for me at 32C/90F ambient temperature is
car velocity of at least 120KM-H / 74.5MPH


Scale on the right is for SPEED only. In KM-Hour
Scale on the left are the temperatures in Celcius. This is me out of a petrol station. So some heat soaked happen during fuel stop.




The charge cooler coolant temperature is my own install and so is the underhood ( engine bay ) temperature.


=======


These below the next 22.54 minutes later when heat soak is almost gone and I can maintain better a bit over 120KM/H or 74.5MPH average.






Hope this thermal strategy info is useful to you............

 

I didnt know about the stat heater, but as long as it doesnt cause problems when it fails its a good thing.
I measure water temp via the ecu, using HP Tuners, which is also how I programmed it to run so much cooler. Mainly the fan settings, then spark timing to more or less fix the idle temp. Plus a slight bump in idle speed. I bumped spark ~10 deg which made all the difference. Today it was ~108F and idle in park was 199F. Oem would be 230.
If you want to log data you should consider HP Tuners. It can display lots of things all at once,
via charts and/or gauges, then you can play it back later. Data speed is limited by the can bus, but cant do much about that.

 

I didnt know about the stat heater, but as long as it doesnt cause problems when it fails its a good thing.
No,you got it the opposite way.
If this heater fail, your engine will then be hotter as the thermostat will open fully only at 102C / 216F

==============

I only have HP Tuner for its Track Addict & Race Render video editor hahaha, but was using other dongle from OBDLink, the simple green color LX
I do not like to tune my engine for its fuel mapping and the like, I keep it stock. Anyhow my 3.0 TT engine is not in the list the MPVI3. covers, albeit MED177 ECM it uses like of M278.

I don't like using a phone as 2nd display, I like permanent wired displays as it is dedicated and fast and it wont fly around during hard driving.
Hence I use Banks Gauge system which is very expandable to include standard OBD2 data MB ECM pumps out and additional sensors from Bank itself and using its own data bus interface.
Minimum logging speed is 5Hz for Banks Data Monster gauge and 20Hz as maximum if using 100 data PIDS, including Banks own proprietary data PIDs where it serve the engine oil pressure sensor ,
the main reason I got the Banks Gauge in the first place.

The only thing I do not like about Banks is it has no GPS data input capability, hence time & date tag is not available in the log file, unlike HP Tuner one, where it uses the smart phone date-time stamp and probably
GPS location too. Banks also can not display M276 3.0 MED177 Lambda value correctly, it shows opposite and in AFR not Lambda.
Can't win all....

 

So the heater directly heats the stat? Does it wrap around it or? I had "assumed" it was heating the water around it since the first opening of the stat is often too delayed in many cars. Well crap, then why do they sell lower temp stats for my car? Seems to me you can just tweak it in the ecu? I'm assuming again, but seems to me you have full control via those wires. People hot wire their intercooler pumps but no mention of this guy? Seems to me it would be ideal to bring the temp down another 20F before a race.
I don't know what Track Addict & Race Render is. I recall seeing it on the website when I bought this setup but it was nothing I wanted. Or maybe I glossed over it too quickly. The data recorder was what I was after, and of course tuning. It sucks you can't tune your car with it, and is also very weird. What could be so different about yours? The HP Scanner is pretty sweet, so I attached a screenshot in case it changes your mind about getting it. Most peoples screens suck, and the generic screen they give you really sucks, but I think mine rocks. I start it before I start the engine, and turn it off after I kill it so I catch everything.

 

The heater is a rod, it is inserted into thermostat body to make metal to metal contact to deliver the heat and melt the wax inside the thermostat in order to make thermostat open sooner than 102-105 celsius.














Replace the complete assy and bring back your timing to original.
Heater has a life and so is the thermostat. Get a new one and while at it replace all those dangerous hoses + aluminum pipe combo to intercooler famous for breaking and leaking



Also, I suggest you go back to MB OE 325.0 coolant as your propylene glycol choice is too heavy/thick for the water pump.
It is as thick as 40W motor oil at 52C/125F, that is so thick.
You loose cooling efficiency even higher by using the propylene glycol not only from its poorer heat transfer but your overall flow will be slower due to such thick viscosity

Simple reference. Water viscosity at 20C is about 1 centipoise only.


Is Centistokes equal to centipoise?
Centipoise = centistokes x specific gravity where specific gravity is assumed to be 0.8 (except for water). To find the exact cp of your fluid: cp = cSt x (weight per gallon x 0.120).
Since the specific gravity Ethy 1.12 and Propy is 1.09 , basically 3% difference only. So the motor oil chart can be used to visualize how thick the propy is.



Thermal conductivity 0.149 btu vs 0.085 is a lot of loss
Holy cow if ethylene is as baseline 100%, the propylene is only 57% for thermal conductivity

 

You are always a wealth of info, and I do appreciate all the data. I especially that pix of the stat out with the rod visible.
I don't have cooling issues, I just want it cooler at idle, but with minimal or no fan, because why not.

The fan was my first tweak to cool idle, but two things were holding me back. One is I don't really want the fan on below 195 or it'll be on while cruising, so I really need spark timing to deal with that. Then there's the T-stat, which seems to have a max low of ~185F, and a high of maybe 195. It seemed odd but now that I know about that heating rod, it makes sense. So for all I know, even pure water won't bring my temps down. And "if" I ever removed the stat housing, which I doubt, I'd likely drill a hole in the stat to lower the temp.

I knew Ethylene is thinner and better at heat X-fer etc, but, and correct me if I'm wrong, Prop is a little better as a water pump lube, better at protecting and lasts longer. Since I'll be using much less of it, the net result will be better than the standard mix of Ethy in it now. Another reason is I don't have to worry about compatibility, or having to remember this one goes in this car, and that in that car, or bike. Prop goes in any and all.

A biggie for me is what happens when it bleeds into the engine oil? Apparently Eth trashes the bearings, Prop does not. I've never seen Eth trash bearings but maybe it's a certain additive, or maybe bearings are different now. Or maybe it's a BS story, but I do know Prop is pretty benign. My eng has an oil to water cooler. If I based my opinion on past experience, it's not a question of it leaking, it's a when. I'm sure this one is less likely to leak but it still makes me very nervous. And how would I feel if did leak into the eng, regardless of how? It's not like I'll tear the eng apart to see if there's damage, so I'd be stressed out from that point on. So in my case, Eth probably won't do anything anyway, but if there was a small gain it would not worth all the negatives.

My intercooler, on the other hand, could use help. So I'll swap out the oem coolant with maybe ~10% Prop and see what happens.
Whatever the case, I already have a gal of Propy waiting to be used. Now that I think about it, I'm not sure I've ever bought Eth.
You know how they say animals will drink coolant? Or at leaast the Eth version? I discovered why. When I was a teen siphoning my radiator out I got some in my mouth. It's pretty tasty! Reminds me of that thick syrup they add to ice to make a Slurpee. At some point they started adding a bitterant.