233 is up there, but if it was brief and you were on it at high speeds a lot then that would be normal.
After the oil mod i notice the oil temp hits target much quicker, and if you drive in comfort at RPM less than 3k often then yes you will see higher temps because the oil is doing its job and pulling heat from the cylinders. However, if you drive more spirited you will see the temps act more stable and actually come down after a pull. Mine will go from 205°F at cruise to 190°F after getting on it. The oil is doing its job but also the tstat for the cooler is fighting to keep you at 190-212.

 

Hmm okay.

So it seems like you also cruise (no pulls at all) within the 200°F range? I'd like to know if there's anything wrong with the oil I use (Molygen 5w40) or my oiling circuit (thermostat/cooler?) before doing the mod. Again I really feel like before I changed the oil to Molygen, my oil temps were lower on average. And that's with oil I believe had ~7k miles on it.

Do you know what your oil temps were like before unplugging the oil valve?

 

FYI guys,
M276.8 does not have actual engine oil temperature sensor, it is a calculated value.
In fact the display of coolant temperature is also rigged, white liar by MB.....unless you use OBD2 gauge, there you get honest coolant temperature...but oil temperature does not exist....as there is no actual sensor for it.



.
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Oh wow... could it be a cost savings measure on MB's end to not include an oil temperature sensor? Hey, it's one less thing to fail right.

Regardless of how the number is calculated, I still take perhaps a bit too seriously?

But y'all... 206F seems a little too hot for just driving around a neighborhood no?

I did a very short pull (shifted at 4.5k RPM in comfort...) up to 55mph on maybe a 17% incline road... and my oil temp registered 210F for a minute before cooling down to 200F.


Am I just overthinking this or is it not quite a bit too hot? Or is it perfectly acceptable for an M276tt?

If it is... I don't even know where to start looking for the issue. Perhaps trying a different oil first?

I guess I'm not used to having a German car with no crippling issues hence a wandering mind

 

Im glad i was able to help you with get rid of from the jerkyness..

What improvements you see apart from jerkyness? do you update just the TCU or ECU as well?

After Oil pump solenoid disconnected, i do have around 103C (engine oil) as normal temp when driving normal and before was between 90-100C and when i decide to push it harder it goes to 110-115C

You see higher temps because oil is constantly circulating and taking the heat (so isn't from your oil) but as MS mentioned the temps are not actual taken from sensors instead calculated based on formula, so not sure when we see 105C engine temps what is the actual temp..

As suggestion for the oil, please look for upgrade with 5w40 SP specification (im using Motul Power which is Ester and absorb the heat better than usual oils and doesn't get burned too quick), i guess your current Molygen one is API-SN? you can find more info about that in the oil pump solenoid thread in short SP specification is better for our engines

 

Im in FL, so this time of the year ill see 5 ish higher temps. Ive also noticed temps can be a little higher with running just 93 vs the E30 blend i normally run.
Ive used Mobil 1 5w40 and 0w40 and have not noticed a discernable temp change between them. Brand shouldnt matter either so long as its full syn, meets MB spec and you are changing it at the recommended 5k interval.
Dont do the oil solenoid mod if you go full interval on oil.

 

I'm actually not too sure about what updates they applied. I actually went in to my dealership for a COMAND firmware update where they stated that they applied other updates as well. But not even five minutes after driving the car I noticed that my transmission no longer jerked between 2-3 gears! And it shifted much "crispily." Not only that, but my Airmatic dampening is much more controlled now. I don't notice any difference with the engine however, you can't fix what's already perfect right.



Hey... now this seems similar to what mine is currently!

I think you might be right about the oil... I was researching Molygen yesterday and found that it might not be the best possible solution for the M276tt. It's better suited for the M156 for its increased wear protection, hence I might end up switching to a different FCPeuro oil change kit. At the moment my options are 5w40 Leichtlauf High Tech from LM or... or... or 0w40 Motul X-Max. I'd like to give Motul a shot but I don't think I need 0w- in Texas where winter is but a rare occurrence

 

I bet you're burning up in FL this summer (me too)
Maybe my oil temp. shift was correlated to ambient temps rather than changing my oil from a dealer fill. All of a sudden I'm not sure what to do now, there are too many variables, so I might just forget about the temps and adjust to my new norm (my M156 sat calmly at 80-90c... but then again, it also waterboarded itself and threw a rod)

Indeed I think 10k intervals are absolutely wild. I've been doing them every 3k since I got my car at 76k mi.

 

in other words... annual 0W-40 oil change are best for leased cars only.

Adopting better oiling practice can help your engine run cooler + cleaner then stronger.

All based on OIL doing all its jobs.

 

0w40 def NO especially if your climate have no real winter, so stick to 5w40 and from the Motul ones there's not so many options with API SP specification - you could pick Motul Power which is only SP spec. or 8100 X Cess Gen 2/X Clean Gen 2 but bear in mind have SN and SP spec and you need SP you can dig in oil thread for other oils that are discussed, don't remember if @CaliBenzDriver mentioned other ones with SP spec. but in terms of price Motul was best way to go

 

Yep, true! Engine oiling is both basic & complex...

Engine runs better on stable oil specs. ie. less than 5kMi. Aged stock oil thins out to become useless.

Black oil is failed oil... easy to spot! No need analysis saying you can go another 20k.Km longer.

0w40 is the same as 5w40!

What's better...

• API-SP cleaner than SN
• Group-IV PAO greater than Group-III "full syn"
• cooler oil better than burning hot
• Clean your bypass valve during oil change
• heavier oil provides a viscosity reserve against heat/aging.

 

• Oil temps will be lower with thinner oil. It will be higher with thicker oil. Thinner oil movies through the engine faster.
• Thicker oil also results in much higher oil pressure which isn't always a good thing as it can contribute to leaks.
• cold oil is thicker. This is why you will notice much higher oil pressure at the same rpm with a cold engine versus a hot engine. Again, higher revs with cold oil can result in pressures that overcome seals and gaskets and hoses. Wait until there is some warmth in the oil before asking a lot of engine.

 

Can you explain this further:Indeed we have seen evidence showing that thin oil is cooler and thicker oil is hotter.

In reference to coolant temps:
Cooler oil accumulates engine heat
Hotter oil removes engine heat
Oil does not store heat in itself but engine does.

Based on that we reach different understanding.
Hotter thicker oil pressure removes heat at lower Rpm.
Oil cooler than coolant is caused by ineffective oiling.

 

Engine oil is a fluid, and fluid moving through a constricted passage has friction against the side walls of a passage. Thicker fluid, more friction. More friction, more heat.

Additionally, (and basically same as above) thick oil requires more work from the oil pump (the pump is pushing fluid though passage ways inside of it). Both the increased friction of the fluid against all surfaces it's flowing passed, and the increase in pump pressure with thicker oil dump heat into the oil.

Addendum, for the same causal reasons stated above thicker oil's greater friction will also generate more heat while it maintains a viscous barrier between rotating assemblies and bearing surfaces.

 

One of the main problems in many modern engines regarding engine oil is the oil is not *ONLY* relied upon to be a *lubricant* but *also* it is relied upon to be a hydraulic fluid.

Actuating hydraulic VVT mechanisms is nothing like retaining film strength in radial and axial loads. The repeated cycling of hydraulic assemblies with degraded/dirty oil has a much more pronounced impact on those mechanisms than dirty/degraded oil has on say, main bearings, timing chains, or piston rings.

 

So you are saying:Mercedes stock features a way to lower your engine oil frictions.
It is done with limited oiling, lower pump pressure and reduced oil viscosity.

The result is stock Euro oil stays colder than the coolant for longer time with less oil frictions.
Stock saves all the way up to 1% gas cost on turbo engines.


The flip side to limited oiling is engine stores extreme heat not removed plus everything related such as stuck pistons rings, carbon deposits shown to bore scores.

 

--
Engine cooling is only an ancillary function of modern engine oil in modern engines, and only for surfaces and components where engine coolant has either no or very minimal access/impact.

There's nothing intrinsically wrong with engine oil being a lower temperature than the engine coolant as long as both fluids are operating in their specified design envelope. Never letting a lubricant get up to optimal operating temps can impact flow characteristics, lubricity, and additive performance, but having the oil over heated (or even constantly in the upper reaches of its operating range) can significantly shorten lubricant life span and reduce over all performance.
This can lead to things like increased oxidation, reduced viscosity, reduced film strength, and increasing volatility.
It's better when systems are designed with all of this in mind (with less focus on other design priorities like fuel consumption), but I really think the fixation with blaming hydraulic system failures on fuel consumption schemes isn't really borne out.
--
VVT systems are, on the whole, performance increasing systems. Yes there are certainly instances where they were employed for decreased emissions, but on the whole VVT/VANOS/VTEC et al were meant to be performance boosters that "replaced displacement" so to speak. And they have ALWAYS, across numerous manufacturers, been sources of maintenance frustration. And I really don't think there's very much that the variable oil pump or extended oil change intervals have to do with it (although the fragility of the variable oil pump solenoid wiring is definitely a sore spot). They are, by design, unreliable and poorly engineered.
--
My own garage is a very small case study.

My car: since my ownership started at 30,000 miles has always had the oil and filter changed every 6 months (and usually less than 5,000 miles) with Castrol Euro 5w40 and a top tier filter. It now needs a new VVT sprocket at under 80,000 total miles.

My wife's car has ONLY ever had *ANNUAL* or 10,000 mile oil changes (whichever came first and a couple of times she went to 12,000 miles between changes), for the first 7 years of its life it was serviced at MB dealerships on a pre-paid annual maintenance plan, and then was converted over to Castrol 5w40 about 4 years ago. It runs flawlessly and has never had a hint of valvetrain noise (or any other problems with the engine other than needing the cam covers resealed). This car has 147,000 miles.

 

There is nothing wrong with cool oil so long you do not relate maters.

Every oil related issue calls for standard maintenance:

• Leaky sensors can be replaced
• "$10k oil in harness" is normal
• carbon valves can be cleaned
• rough shifts can be adapted
• pistons build-ups can be removed
• misfires can use many parts attempts
• rear main seals require engine out
• combustion chambers buildup
• bore scores are terminal: no sleeve!

Limited oiling is good to "save on gas".
Ownership experience varies between owners.
Big repairs end up as trade ins or crushed.