I'M SO CONFUSED

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I HAVE AN 11.1 LITER DETROIT DIESEL IN MY BIG TRUCK. IT HAS 815000 MILES ON IT.IN SPITE OF THE MILEAGE IT ALWAYS GAVE GOOD OIL ANALYSIS RESULTS. I USED THE MOBIL DELVAC 15W-40.

ALUMINUM 2
CHROMIUM 2
IRON 12
COPPER 3
LEAD 1
TIN 1
SILICON 3
POTASSIUM 0
SODIUM 2
THIS WAS WITH 11,500 MILES ON THE OIL.

THIS IS WHERE I MESSED UP. I CHANGED TOO MANY THINGS AT ONE TIME. I INSTALLED A SPINNER II OIL CENTRIFUGE, CHANGED TO MOBIL DELVAC 1 SYNTHETIC (5W-40), AND CHANGED ANALYSIS COMPANIES.

AFTER 14,250 MILES ON THE SYNTHETIC HERE ARE THE RESULTS.

ALUMINUM 3
CHROMIUM 5
IRON 20
COPPER 11
LEAD 3
TIN 0
SOOT 0.9
TBN 9.1
SAE 43
OXIDATION VISC@100 13.7
GLYCOL NOT DETECTED
SILICON 9
POTASSIUM 16
SODIUM 6

EVERYTHING WAS NORMAL WITH ALL THE SAMPLES, BUT WHY DID THE WEAR METALS INCREASE SO MUCH WITH THE SYNTHETIC AND THE BYPASS FILTER. THE PURPOSE OF CHANGING ALL THIS WAS TO REDUCE WEAR. THE FILTER REMOVED A LOT OF SOOT, SO I ASSUME IT IS REMOVING WEAR PARTICLES ALSO. THE SYNTHETIC HAD MORE MILES ON IT BUT NOT ENOUGH TO JUSTIFY THAT MUCH INCREASE IN WEAR METALS. SO HERE ARE MY QUESTIONS.

COULD THE DIFFERENT LABS MAKE THAT MUCH DIFFERENCE?

SHOULD I GO BACK TO THE DINO OIL? IT SHOWED LESS WEAR.

COULD THE SPINNER II BE ADDING WEAR METALS? IT IS SUPPOSED TO SPIN AT 5000+RPM'S. IT HUMS FOR QUITE SOME TIME AFTER I TURN THE ENGINE OFF.

THANKS IN ADVANCE FOR ANY IDEAS.

I JUST NOTICED: COULD THE INCREASE IN SILICON HAVE DONE IT??


JESUS IS MY COPILOT
 
GMC,

Delvac 1 has excellent detergency and solvency properties due to the organic esters used in the formulation. What you are seeing is the preexisting sludge/varnish/carbon deposits being cleaned out and held in suspension. Some of the metal which was previosly worn off the internal parts of the engine is incapsulated by these deposits, so when they go into solution they show up as increased wear. These deposits tend to be highly acidic, so they can also cause some initial TBN depletion. I see this all the time when a high mileage engine is changed over to synthetic oil ....

Delvac 1 is an extremely good synthetic oil, in fact I think it's the best product that Mobil makes. Keep running Delvac 1 and I'm very sure these wear rates will come back down by the second or third analysis ....

TooSlick
Dixie Synthetics
 
THANKS FOR THE REPLIES.
IT MAKES SENSE NOW.
GOOD TO HEAR I DIDNT WASTE MY MONEY.

DUE TO THE EXPENSE, I DONT WANT TO CHANGE THE OIL UNTIL I HAVE TOO. BASED ON THE FIRST ANALYSIS CAN ANYONE VENTURE A GUESS AS TO HOW MANY MILES THIS OIL WILL GO???
I PLAN TO TEST IT EVERY 15,000 MILES.

THANKS AGAIN
 
How many miles? Depends on lots of things--the driver's skill at carefully handling the engine load is one, truck's loaded weight, mountains?, short idle time, little or no city driving, engine wear condition, choice of filters (the spinner is good, as is a bypass filter).

30,000 should be no problem, and if everything in your control and some things outside your control are good, maybe 60,000.

Have you looked into Schaeffer #700 15W-40? It's probably as good an oil and costs about $10/gallon.
http://www.schaefferoil.com/data/700.htm


Ken

[ April 24, 2003, 01:16 PM: Message edited by: Ken2 ]
 
Question, any measurable increase in fuel mileage since the change to Delvac 1.

The marketing for 5W-40 synthetics vs 15W-40 dino HDMO's claim fuel efficiency as the main advantage, along with easier cold weather starting, not necessarily decreased engine wear. I'm talking here about marketing aimed at the big fleet operators from the major oil companies like ExxonMobil and Shell.
 
I REALLY CANT SAY I'VE NOTICED A CHANGE IN FUEL MILEAGE(A LITTLE DISAOPPOINTING). IT WOULD BE DIFFICULT TO TELL WITH ONE TRUCK THOUGH AS FUEL MILEAGE VARIES WITH SPEED, LOAD, WIND, HILLS, AND TRAFFIC.

I FOUND SCHAEFFERS AFTER I STARTED ALL THIS. IT DOES SOUND LIKE A GREAT OIL, ESPECIALLY FOR HIGHER MILEAGE ENGINES LIKE MINE. I'M GOING TO TRY THE SCHAEFFER GREASE AND PRABABLY THE GEAR OIL FOR THE TRANSMISSION AND REAR ENDS. SINCE I STARTED WITH THE DELVAC 1 I'LL GIVE IT A FEW CHANGES TO SEE WHAT HAPPENS.

AS FAR AS EXTENDED DRAIN INTERVALS, WHICH ONE WOULD LAST LONGER THE SCHAEFFERS OR THE MOBIL DELVAC 1.
 
GMS,

Theoreticallly, the Delvac 1 should give you higher drain intervals because of the thermally stable base stocks. The Schaeffer's #700 is no weakling, since it has an excellent additive package.

Please do post later analysis with all elements if possible. I am very interested in seeing your results.
 
You didn't say whether the Detroit engine was four cycle or two. From the oils used I would assume it is 4 cycle, so we won't blame the ash content for any buildup's.
As said, probably the synthetic cleaning it up. How far per change depends a lot on the factors mentioned above. The engine has a lot to do with it too... Volvo has some engines approved for Delo 100,000 km between changes. But that is not all engines under all conditions. Analisis and documented conditions is the best answer. I also have a couple of pages on that subject on my site if you can handle the spanish.
http://american.netfirms.com/Seleccion/Frecuencia/frecuencia.html
http://american.netfirms.com/Seleccion/Extension/extension.html
 
  • The wear is good with the petro oil?
  • Can the Delvac 1300 be run longer?
  • Is the reason for the syn oil longer changes or less fuel consumption?
  • Keep us informed ,please
 
THE ENGINE IS A 4 STROKE(SORRY WIDMAN, NO HABLO ESPANOL). I DO NOT IDLE THE ENGINE FOR ANYTHING MORE THAN ABOUT 15 MINUTES. AS FAR AS DRIVING HABITS GO I'M PROBABLY A LITTLE HARD ON IT. IT ONLY HAS 300 HP OFF THE PEDDLE, SO DURING ACCELERATION ITS ON THE FLOOR. IT TAKES ABOUT A MILE TO GET UP TO 60MPH, AND THATS WITH A RELATIVELY LITE LOAD (GUESSING AROUND 60,000 GROSS ON A NORMAL LOAD).THE 11.1 LITER ENGINE IS MADE FROM THE SAME BLOCK AS THE HIGHER HP 12.7 LITER ENGINE, SO ITS OVERBUILT FOR THE HORSEPOWER OUTPUT. THE ENGINE IS ALSO COMPUTER CONTROLLED(DRIVE BY WIRE). FUEL MILEAGE IS BETWEEN 5.8 AND 6.7 NORMALLY ABOUT 6.25 MPG. MOST OF IT IS FAIRLY FLAT LAND AND HIGHWAY.

THE MAIN REASON FOR ALL THIS IS EXTENDED DRAIN INTERVALS,HOWEVER IF THE INCREASED WEAR CONTINUES I'LL GO BACK TO THE DELVAC 1300. I'M NOT SURE HOW LONG DRAINS COULD BE EXTENDED WITH IT THOUGH.
 
Relative to the changes in your oil's measured values using oil analysis, consider this:

When testing anything, one must consider what is statistically significant. The ASTM has standards known as Repeatability and Reproducibility.

  • Repeatability is a measure at 95% Confidence Limit for back-to-back repeat measurements and is a surrogate for precision.
  • Reproducibility is a measure at 95% Confidence Limit for duplicate measurements made of the same material in different laboratories and is a surrogate for accuracy.
As you have changed oil analysis laboratories, reproducibility has definitely come into play. What you need to do now is re-establish your confidence in repeatability with the new lab by watching for new trends as you continue your used oil analysis. You may need to test more often to re-establish that confidence.

As for the actual wear metals you're seeing, they're relatively insignificant at this time. See this bobistheoilguy.com article on acceptable wear metal levels using oil analysis.
 
GMCDURAMAX,

Why did you change all that stuff? Although I didn't see your FTIR results the wear elements looked good. I am guessing you could extend a little with conventional oil but I would like to see FTIR. I've not seen a case where the synthetic diesel oils resulted in being able to extend the oil drain periods significantly in diesel engines, mainly because soot is usually the limiting factor. Syn oils are great for cold weather or desert operation, but it usually is not cost affective. I have access to some good data from mileage test done using a 5W40 oil and in some cases it showed a slight increase and in others no change or even a slight decrease. The conclusion was there was no significant change in fuel economy.

You didn't post the zinc level and right off hand I can remember the levels for these oils but I am assuming they are around 1200 ppm or so. Since the spinner filer removes particles such as soot, and since the zinc anti-wear additives adsorb to surfaces, including particles such as soot, you can actually be removing this additive. During normal operation the OEM filters do a good job of removing debris so additional filtering is not needed. True additional filtering can remove smaller particles, but in most cases the cost cannot be justified.

My advice is to use good quality filter (preferably OEM) and use a premium oil the meets the engine manufacturer's specification. Take oil samples at each change and make sure your analysis includes viscosity and FTIR. PQ also provides valuable information about the presence of large iron particles that do not show up in the Iron readings.

Good luck
Stinky
 
"Delvac 1 has excellent detergency and solvency properties due to the organic esters used in the formulation"

This is not an ester-based oil. It is a PAO (unless they changed the formula). The easiest way to tell is to look at the oxidation. I am used to a different scale than the one reported but you will see super high readings if an ester is present.

Stinky
 
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