Liquidcosworth

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Interesting discussion I came across HERE
LQ is a member here too but he offered some good info on this site.

quote:

Hello all.

I would like to agree that Total Base Number does neutralize acids caused by combustion by-products, but it does not keep contaminants in suspension.

To a large degree, the acidic combustion byproducts are a result of a reaction with sulfur in the fuel. With the introduction of low sulfur gasoline in the US several years ago (sulfur in gasoline cause the rotten egg smell) and the imminent introduction of low sulfur diesel fuel (because sulfur contributes to particulate emissions) the balance of good performance oil formulations has tipped away from high initial TBN. And in practice, the many additive types that provide TBN have different initial values and consequently the better measure is TBN retention.

The additive that keeps contaminants in suspension is a dispersant. High dispersancy prevents sludge "puddles" and oil thickening. As a side note, it may even cause a new oil to turn dark quickly, since it picks up deposit related materials left from the previous oil charge

quote:

We use a blend of PAO and esters. PAO tends to shrink seals, esters to soften them, so a mixture is ideal for elastomeric materials to maintain the original shape. Also, we prefer to formulate with friction modifiers (we use two distinct families of FMs) to provide that activity on the metal surface rather than polar ester base oils.

Our approach is to ensure maximum engine performance and reliability. To that end, there is (to over simplify) a dual system of detergents, dispersants, anti-wear, and friction modifier systems in the formulation. One group covers the performance needs of street performance, gasoline engines, and moderately severe temperatures. The other group performs in the higher temperature arena of diesel engines. In north America, think of turbo-charged tractor trailers that operate at high loads for extended periods, passing significant quantities of soot, blow-by and fuel components into the oil. Those conditions represent racing conditions reasonably well.

Historically, not using detergents was an artifact of some racing engines consuming oil. Organo-metallic additives would cause combustion chamber or piston top deposits, leading to pre-ignition. That's not the case in modern engines. The only technical challenge is balancing the activity on the metal surface between detergents and friction modifiers, which can be done. Motul 300V products do have calcium and magnesium detergents

quote:

We use a diester rather than polyol esters and formulate with the additive(s) to manage the overall formulation characteristics.

The F1 engines run to 19,000+ and use 0W-20.

No, you can't tolerate wear and still expect to have low friction. Low friction is the sum of low fluid friction (oil pump effort, hydrodynamic bearings) and low boundary lubrication (valve train, cylinder walls.) The first is a function of viscosity, the second is a function of additives that are bound to the metals surfaces.

TBN is only a measure of the chemical strength to neutralize acids, and is also only a point of reference for when the oil is new. It helps to control corrosive attack from the exhaust blow by, especially if it chemically reacts with sulfur in the fuel. Initial TBN does not predict TBN retention, or how long this performance lasts. By itself it's not necessarily a good indicator of change interval length.

The focus is on engine performance and reliability; not necessarily fuel economy or extended drain (although those attributes are there.) Low friction, protection in all engines under the broadest performance envelope, and durability of the oil are key. Read more by clicking the "technical" button on the engine oil product page on our site.

I can't say if any other oil companies sell exactly the same formulation. I mean that even if I knew, I could not tell. But read the advertising...

As touched on above, a thinner oil with proper additive treatments, will provide a benefit. The practice depends on somewhat on monitoring oil temperatures, engine components that use the oil as a hydraulic fluid (variable valve timing controls) and oil pump pressure settings.

The oiling system has a certain amount of "spillage and splash" to lubricate valve trains and cylinder walls. This depends on mechanical design such as the diameter of a squirt nozzle. You would want to know if the oil pump has enough volume and pressure to prevent bleeding down too much at the end of a lubrication passageway.




[ August 26, 2006, 01:15 PM: Message edited by: Bio-T ]
 
It's be interesting to see them run their 0w30 in the Sequence IIIG, IIIGA, VG, and IVA tests (not for API cert.) and report the results. An expensive proposition, but a heck of a marketing tool for oil geeks like us.
 
The only down side of preaching TBN retension is that it can only be measured by the average joe by useing it and testing with UOA. Last I checked their was no reporting of TBN retension as an ASTM test listed on most or any oil company white papers. I do agree that TBN retension is more important then total starting TBN. I think though that when most of are compareing total TBN we usualy are compareing like products both in market segment and price point. If you look at most of your premium products like Motul,Penrite,Fuchs,Amsoil,Redline,Mobil-1EP most of them behave very simalar in terms of TBN retension when used in the the same vechile dureing seperate OCI's. It would be wrong to compare a high total TBN store brand dino 15W40 to say Amsoil S3K 5W30.

Much of what he said has been said many times over and over again on this site. Molakule has preached to use what the various elements are that make up an effect additive package and what they do. TBN is about preventing corrosive damage from blow-by not about cleaning the engine.

I think it is still reasonable though with longer and longer OCI's to pick an oil with a high initial TBN over a lower TBN until you know what it's retension charteristics are! You would not pick a dreadful tasteing wine for your collection hopeing that it would get better with age! Instead you would pick a wine that already tastes good if not great and hope that it would only get better with age. So always use best practices to start with and refine your plan or practices as data determines latter. Their is nothing wrong with changeing a plan as data or experince dictates but not haveing a plan and simply reacting is not good.People seldom plan to fail but they often fail to plan!!
 
Actually JB, testing for TBN retention is done by some European OEM's...For example a minimum TBN is required at the end of the VW "T-4" high temp test (part of the VW 502.00 spec). This test runs for 248 hours and does not allow the addition of ANY makeup oil, in contrast to the API Sequence IIIG test.

TS
 
After looking up the VW T4 test procedure, it doesn't look like it's significantly more difficult than the comparable API/GF-4 tests, given the way it's rated. The 216 Hr Sequence VG is probably the better comparison and it measures TBN.
 
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