After 5k them additives start to deplete and oil should be changed.After how many miles does the anti wear additives (like zinc, phosphorus etc..) depletes from the oil (approx.) ?? does it deplete as fast as the other additives like detergent or dispersants ??
Only if the additive in question is being "plated out" onto surfaces or otherwise being physically removed from the oil. A spectrographic analysis only measures elements that are decomposed from a compound, so if the additive is degrading somehow (such as oxidation) then the total amount of element the original compound held will still show up the same on a UOA. Spectrographic analysis does not show compounds.I think we will get the answer if we get the additive value for new oil and then for used oil at various mileages. Ed
That's probably based on the TBN or some vague serviceability recommendation. I doubt Blackstone (or anyone else for that matter) bases an OCI recommendation on the antiwear additive levels as the OP is asking about.I'd say a lot of factors are in play here. I ran Wolf's Head 5W-30 for 12,000 miles (GMOLM) in a 2004 Chevy truck, 5.3. Sent a sample to Blackstone and they said it could go longer.
This was long ago, like 2005 or 06.
Yeah - BASF & EMRE have worked on metal free additives - do you think that’s more for the M1 ESP lines ?Only if the additive in question is being "plated out" onto surfaces or otherwise being physically removed from the oil. A spectrographic analysis only measures elements that are decomposed from a compound, so if the additive is degrading somehow (such as oxidation) then the total amount of element the original compound held will still show up the same on a UOA. Spectrographic analysis does not show compounds.
The other problem is that some additives are not metal based and organics do not show up on a standard UOA. Elements such as carbon, nitrogen and oxygen are not able to be analyzed in an ICP. Even if they were the oil itself is full of those elements. FTIR would be of some help here but that's not part of a standard analysis.
Thanks for that, so they were using mass spec for their analysis.A Comprehensive Chemical Assessment of Engine Oil Degradation in a Passenger Car.
For the understanding of oil degradation in a combustion engine, in particular zinc dialkyl dithiophosphate (ZDDP) deterioration and its impact on wear expressed as iron content, a field test with a passenger car was carried out, which covered a distance of 19,800 km and represented an entire oil change interval. Condition monitoring of the SAE 5W-30 engine oil used in the turbocharged petrol engine combined the use of conventional and advanced analytical methods.
The conventional data collected from the used oils revealed the progress of additives (antioxidants, base reserve, ZDDP), oil degradation products (oxidation, nitration, sulfation, acids), and contaminations (water, soot, wear, fuel dilution). High-resolution mass spectrometry was included to identify ZDDP additive compounds and their fate during the field test as well as their correlation with wear formation. Dialkyl dithiophosphates as the main ZDDP compounds were rapidly degraded and no longer detected after 6000 km. Dialkyl thiophosphate as intermediate ZDDP degradation product was formed and largely depleted within the first 6000 km. Dialkyl phosphates, phosphoric acid, and sulfuric acid as organic and inorganic ZDDP degradation products were generated early and reached high levels at the end of the field test.
The presence of intact ZDDP and its degradation products, notably phosphoric and sulfuric acid, correlated with the oil’s iron content. Wear largely remained at low level as long as intact ZDDP was available for tribofilm formation. The lack of ZDDP along with the formation of inorganic acids from ZDDP resulted in an increase in the wear rate by a factor of four.
Thanks alot, very informative,A Comprehensive Chemical Assessment of Engine Oil Degradation in a Passenger Car.
For the understanding of oil degradation in a combustion engine, in particular zinc dialkyl dithiophosphate (ZDDP) deterioration and its impact on wear expressed as iron content, a field test with a passenger car was carried out, which covered a distance of 19,800 km and represented an entire oil change interval. Condition monitoring of the SAE 5W-30 engine oil used in the turbocharged petrol engine combined the use of conventional and advanced analytical methods.
The conventional data collected from the used oils revealed the progress of additives (antioxidants, base reserve, ZDDP), oil degradation products (oxidation, nitration, sulfation, acids), and contaminations (water, soot, wear, fuel dilution). High-resolution mass spectrometry was included to identify ZDDP additive compounds and their fate during the field test as well as their correlation with wear formation. Dialkyl dithiophosphates as the main ZDDP compounds were rapidly degraded and no longer detected after 6000 km. Dialkyl thiophosphate as intermediate ZDDP degradation product was formed and largely depleted within the first 6000 km. Dialkyl phosphates, phosphoric acid, and sulfuric acid as organic and inorganic ZDDP degradation products were generated early and reached high levels at the end of the field test.
The presence of intact ZDDP and its degradation products, notably phosphoric and sulfuric acid, correlated with the oil’s iron content. Wear largely remained at low level as long as intact ZDDP was available for tribofilm formation. The lack of ZDDP along with the formation of inorganic acids from ZDDP resulted in an increase in the wear rate by a factor of four.
Stuff like ZDDP doesn't deplete, it gets constantly recycled in the engine. Detergents and dispersants load up, VI improvers shear, and oxidation starts setting in, that's why oil must be changed.After how many miles does the anti wear additives (like zinc, phosphorus etc..) depletes from the oil (approx.) ?? does it deplete as fast as the other additives like detergent or dispersants ??
It degrades and no longer can perform the intended function. Here is an article that describes using NMR to track the depletion:Stuff like ZDDP doesn't deplete, it gets constantly recycled in the engine. Detergents and dispersants load up, VI improvers shear, and oxidation starts setting in, that's why oil must be changed.
Thanks alot, very informative,
I watched some YouTube videos about oil analysis and it appears that zinc and phosphorus can last up to 10,000 miles from test results,
Here are the videos:
I think Test results only show the ppm of zinc and phosphorus regardless if they are functioning or notWhere in those videos are they measuring intact and functioning ZDDP?
Yes that’s why I asked?I think Test results only show the ppm of zinc and phosphorus regardless if they are functioning or not
Right, Zinc and Phos will still show up on UOA because it has not 'disappeared'.I think Test results only show the ppm of zinc and phosphorus regardless if they are functioning or not