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If you could remember, when I made my last oil change and when I reported here, I was filling 7L of 5W40 and 1L of 5W50 from the beginning. And when I was filling up the 300ml after 6000Km, I put 5w50 inside. The oil looks after 6000Km really perfect. Like Honey. 😍
So I think the engine was pretty good prepared for the swap to 5W50. This time it will be the 3rd oil change since unplugging oil solenoid.
My plan is to change the oil and after that, we will made a trip with the kids for about 100Km in one direction and 130Km back. So the engine will gets a little bit time to learn to handle the new viscosity and made some adaptations to the timing. 😀👍🏻
You've got it! A little 'preview-mixing" is nice easy way to step up the ladder smoothly.
Long drives like 100Km are excellent for oil spraying and ECU/TCU learning... and so much fun to play with increasingly responsive throttle.
Enjoy all the rewards of your MOD-X upgrade experimentation.
Last edited by CaliBenzDriver; Dec 1, 2025 at 04:52 PM.
I think there's valuable data points in this video's experiment and commentary on results and, it seems relevant to this thread
knowing all that oil filter topic you've reviewed, do you now believe MB inverted filter...:
-- drains out to start dry each time
or
-- does the oil stay air locked inside the housing?
Last edited by CaliBenzDriver; Dec 1, 2025 at 10:50 PM.
knowing all that oil filter topic you've reviewed, do you now believe MB inverted filter...:
-- drains out to start dry each time
or
-- does the oil stay air locked inside the housing?
I’m pretty sure the oil drains from the filter. I wouldn’t call it “dry” though. When you remove the filter housing, if it was full of oil, the oil would spill all over. Or, maybe as you unscrew the housing you break any vacuum seal that would keep oil in the housing and it drains immediately into the oil pan. Either way, there are lots of examples of oil filters being on top of an engine indicating that it isn’t a flawed design. Not sure it is anything I would worry about. Of course, I tend to worry only about things I have control over.
i need to find it again - new video out on why US cars ask for 0 weight oil and the exact same car in Europe call for 5 or 10 (lower) weight. It all boiled down to keeping Environuts happy. Well, and the banks who in general finance the replacement cars.
[QUOTE=OldManAndHisCar;9240058]i need to find it again - new video out on why US cars ask for 0 weight oil and the exact same car in Europe call for 5 or 10 (lower) weight. It all boiled down to keeping Environuts happy. Well, and the banks who in general finance the replacement cars.[/
i need to find it again - new video out on why US cars ask for 0 weight oil and the exact same car in Europe call for 5 or 10 (lower) weight. It all boiled down to keeping Environuts happy. Well, and the banks who in general finance the replacement cars.
I watched that youtube video, as well. Was this it?
There's a lot of arguments including rebuttals in this video.
Here is a transcript near the 10mn time mark:
10:50 - At those high temperatures, the protective film from 0W20 oil starts to break down.
As the oil begins to evaporate there will be more metal-on-metal contact.
This will cause significant engine wear, leading to repairs in the thousands of dollars.
In other situations, the oil cokes onto the hot piston surfaces, which then hinders ring movement and reduces efficiency
11:16 - You'll get a lot of piston scuffing which can cause overheating, increased vibrations, and loss of engine power.
11:24 - This is where 5W30 comes in handy.
At temperatures above 250 degrees Fahrenheit, 5W30 maintains 50% greater film thickness than 0W20.
....
The transcript establishes known relationship between related facts:
piston heat
burnt oil
dirty rings
compressions losses
engine vibrations
unbalanced contributions
Burntoil is the result of limited squirters effectiveness causing accumulated pistons heat.
(We've seen Toyota V6-TT GDI uses twin-squirters with gear-pump to provide effective pistons cooling Clean rings provide best combustion seals. Perfect setup ).
My experimental solution is to remove pistons heat to cleanrings groves.
> Whatever it takes to not burn oil...
greater lubricant
more spraying
less friction
Engine vibrations evidence the unbalanced cylinders losses: a call for action.
The choice of oil specs are dictated by the engine type, size, application, locale, SAE/EPA,...
W16/W20: savings + bearings killer
W30 : base effective lubricant
W40 : viscosity widely compatible
W50 : higher temperature protection
The initial viscosity provides a reserve.
After 1,500.Miles hot GDI oil shades viscosity according to lubricant grade:
W40 derates in upper W30
W50 derates as a premium W40!
Last edited by CaliBenzDriver; Dec 2, 2025 at 09:40 PM.
Yesterday, I spoke to an engineer from the world of motorsport (Sauber F1 Team) and he gave me some important information about 5W40 vs. 5W50.
The cold viscosity of the two oils is almost identical, as both have a 5W rating. So when cold, one is no more or less thicker than the other.
BUT... at an oil temperature of 100 degrees, 5W50 is between 30-33% thicker than 5W40 and therefore offers much more stable viscosity. The dilution by gasoline is also significantly lower than with 5W40. He has conducted and analyzed numerous tests, as his car has a V6 bi-turbo with almost 600 hp. Good lubrication and some reserve in the oil are very important for him.
Yesterday, I spoke to an engineer from the world of motorsport (Sauber F1 Team) and he gave me some important information about 5W40 vs. 5W50.
The cold viscosity of the two oils is almost identical, as both have a 5W rating. So when cold, one is no more or less thicker than the other.
BUT... at an oil temperature of 100 degrees, 5W50 is between 30-33% thicker than 5W40 and therefore offers much more stable viscosity. The dilution by gasoline is also significantly lower than with 5W40. He has conducted and analyzed numerous tests, as his car has a V6 bi-turbo with almost 600 hp. Good lubrication and some reserve in the oil are very important for him.
I’d be curious what the difference between 5W-40 and 5W-50 is at normal operating temperature. Was the 100 degrees Celsius or Fahrenheit? If Fahrenheit, then 100° is too cold to run the engine hard.
I’d be curious what the difference between 5W-40 and 5W-50 is at normal operating temperature. Was the 100 degrees Celsius or Fahrenheit? If Fahrenheit, then 100° is too cold to run the engine hard.
> OIL SPECS...
To know the difference between a 5w40 and 5w50 oil you should lookup the individual oil specs you are interested in [done this earlier in this thread].
> 5W-40 RANGE...
Be aware that a 5W40 Euro FS is very different from a 5W40 PAO.
Each individual oil has a different set of ATTRIBUTES that make up its profile.
ALL oils are marketed as the best until put to the test: rapid viscosity drop is then coined as "gas savings".
- Group III: SYN favor lower cost + gas savings. - Group IV: PAO favor heat stability + performance.
oils viscosity chart
All 5w40 have different numbers that fall within the same W40 viscosity range.
Once you find improvements from the top of W40 oils then you seek further results in the low W50... MOD-X.
> Your Question:
100° in Celcius relates crankcase oil temperature, that's near 200° on the Fahrenheit scale.
The oil really does not work at 100°C but MUCH GREATER TEMPS around the cylinders bores.
Oil temp is remotely related to piston rings temps.
> What's Happening:
-- Oil gets hotter by effectively cooling pistons:
-- Oil stays cool by not spray cooling pistons:
Hotter working oil is a good sign that engine heat is being circulated to prevent extreme accumulation.
> NOT ONLY WORDS... $$,$$$
You want a setup that gets working oil hot to keeps clean rings sealed.
ELSE high blow-by is $10K when rear main seal acts as crankcase relief.
Listen to video story: hot pistons vaporized enough oil to built up carbon in PCV shut - That blew up the rear main seal for relief at 50kMi. New parts get swapped but root cause is left untouched for next round.
Reported lifespan possibility up to 150kMi.
> SIMPLE CORRELATION :
-- We can not measure our pistons temperature or rings seal effectiveness.
-- We can not measure crankcase blow-by pressure
-- We can however easily read the brake booster vacuum sensor which we know is directly linked to crankcase blow-by that is linked to rings seal ie. cooling by non-burning oil.
Ppl experimenting with oil upgrade can recall the improvement in brake pedal from better vacuum in brake booster, right?
What I'm saying is the good/bad brakes vacuum level is a quick marker of RINGS SEAL/losses.
Last edited by CaliBenzDriver; Dec 3, 2025 at 11:50 PM.
> OIL SPECS...
To know the difference between a 5w40 and 5w50 oil you should lookup the individual oil specs you are interested in [done this earlier in this thread].
> 5W-40 RANGE...
Be aware that a 5W40 Euro FS is very different from a 5W40 PAO.
Each individual oil has a different set of ATTRIBUTES that make up its profile.
ALL oils are marketed as the best until put to the test: rapid viscosity drop is then coined as "gas savings".
- Group III: SYN favor lower cost + gas savings. - Group IV: PAO favor heat stability + performance.
oils viscosity chart
All 5w40 have different numbers that fall within the same W40 viscosity range.
Once you find improvements from the top of W40 oils then you seek further results in the low W50... MOD-X.
> Your Question:
100° in Celcius relates crankcase oil temperature, that's near 200° on the Fahrenheit scale.
The oil really does not work at 100°C but MUCH GREATER TEMPS around the cylinders bores.
Oil temp is remotely related to piston rings temps.
> What's Happening:
-- Oil gets hotter by effectively cooling pistons:
-- Oil stays cool by not spray cooling pistons:
Hotter working oil is a good sign that engine heat is being circulated to prevent extreme accumulation.
> NOT ONLY WORDS... $$,$$$
You want a setup that gets working oil hot to keeps clean rings sealed.
ELSE high blow-by is $10K when rear main seal acts as crankcase relief.
Listen to video story: hot pistons vaporized enough oil to built up carbon in PCV shut - That blew up the rear main seal for relief at 50kMi. New parts get swapped but root cause is left untouched for next round.
Reported lifespan possibility up to 150kMi.
> SIMPLE CORRELATION :
-- We can not measure our pistons temperature or rings seal effectiveness.
-- We can not measure crankcase blow-by pressure
-- We can however easily read the brake booster vacuum sensor which we know is directly linked to crankcase blow-by that is linked to rings seal ie. cooling by non-burning oil.
Ppl experimenting with oil upgrade can recall the improvement in brake pedal from better vacuum in brake booster, right?
What I'm saying is the good/bad brakes vacuum level is a quick marker of RINGS SEAL/losses.
These are always awesome. Great intel and thanks for it.
I use LIQUI Moly 0W-40 or 10W-40 runs awesome with the soleniod unplugged
I thought the brake booster vacuum was generated by the vacuum pump and not crankcase pressures.
Of course, I’m just learning, so I may be wrong.
Yes, our engine like so many these days uses a dedicated vacuum pump to generate all necessary vacuum power for:
brake pedal booster
TT wastegates control
Intake plenum flap actuators
> V-Pump: CRANKCASE AIR + OIL...
Where it's confusing is that the pump breath in and breath out of the crankcase space
Meaning it pumps down a vacuum from the blow-by pressure: ouch!
-- Crankcase is also where excess pump lube is returned back to oil sump.
-- Crankcase pressure is based on blow-by pressure minus PCV venting.
Lets see what can be done to help all that run better than new....
> Pressure/vacuum laws...
Practically that means the vacuum level is referenced or depends on the crankcase pressure level:
More crankcase positive pressure = less booster negative vacuum
less crankcase positive pressure = more booster negative vacuum
> LINK BETWEEN PRESSURE vs. VACUUM...
During the course of experimental oil upgrade at the stage where pistons seals are cleaning up well, the brake pedal noticeably starts becoming very good: touchy & strong instead of hard + less responsive.
My stock MOD-0 brake booster was often found flat empty ever since car passed 1Yr old.
You know hard to "push pedal to start"? Thats from a poor vacuum fill.
Now my vacuum booster is still filled after 26 days and I have done nothing to it beside MOD-X.
It don't particularly care about the brake booster but if it works as factory new, it says something.
my ESP/ABS shows -1Bar (-14Psi) vacuum sensor at idle
> PRESS. CALCULATIONS...
+ Vac pump output shown as: -14Psi vacuum
+ Air pressure at sea level: +14Psi pressure
+ Engine idle crankcase blow-by : (+10psi pressure)
= Pumps manages to pump down more than 40psi... right?
Brake booster has its own check-valve to hold back on the lowest vacuum found near idle. So that brake booster at 50mph is using the best stored idle vacuum.
Circuit has 3 check-valves: 2 for brakes + 1 misc.
> Experiment decreasing your crankcase blowby simply by sealing your cyl. contributions.
- We don't care much about vacuum level only to the extent it evidence poor ring seal that significantly degrade ECU+TCU driveability.
++++ WASTEGATES VACUUM...
We can wonder how different vacuum level in wastegates affects turbo boost operations like it does to brakes ??
... I have not tested that relationship...
We've seen what the pump "small silicon check-valve" does to wastegates with poor vacuum, this is similar... slowed wategates reactions.
> SIGNIFICANT RELATIONSHIPS: AIR PRESSURE + GAS VOLUME...
(nothing new, more focussed)
To experiment we don't have to measure exactly to evidence significant variations.
What messes up the driveability is the unstable cylinder pressure caused by rings losses.
ECU computes a nearly precise gas combustion based on a precise volume of air:
Ring losses screw up fuel maps that deliver lean throttle.
To gain rich throttle response we simply help ECU build accurate maps with reliable cyl. pressures... MOD-X is not rocket science!
Last edited by CaliBenzDriver; Dec 4, 2025 at 02:14 PM.
I’d be curious what the difference between 5W-40 and 5W-50 is at normal operating temperature. Was the 100 degrees Celsius or Fahrenheit? If Fahrenheit, then 100° is too cold to run the engine hard.
Hi Everyone, I know this is an old thread. I am the new owner of a 35k miles 2019 GLE 63s non coupe. Had it for about 6 months. I stumbled onto this mod a couple weeks ago. Full transparency I have had BMW's my whole life.......
Anyway, I unplugged the solenoid last week and it throws a Check engine light on the second engine start cycle every time it cleared after being unplugged. Also seems to be down on top end power a little but I could just be making that up.
Everything seems back to normal when its plugged in.
Any suggestions to trick it into thinking its plugged in?
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