Explain these 2 Redline characteristics: Oxidation and TBN

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Both values seem to be unusually elevated for this oil. Do these numbers decline with long term usage? Per Note* Both Redline and Royal Purple web sites say that there proprietary oil chemistries need multiple oil changes for cleaning affects (wear values) to stablilize.
 
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quote:
Originally posted by outrun: Both values seem to be unusually elevated for this oil. Do these numbers decline with long term usage?
Are you asking if the oil oxidises less and TBN retention gets better over time ? Both Redline and Royal Purple web sites say that there proprietary oil chemistries need multiple oil changes for cleaning affects Mobil Supersyn literature say's something to this effect as well . [ April 06, 2004, 06:29 AM: Message edited by: Motorbike ]
 
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Oil oxidation is quantified by using Fourier Transform Infared Spectroscopy or "FTIR" and looking for the presence of carbon-oxygen double bonds, called "carbonyl" groups. The three major species formed by oxidation - Aldehydes,Hydroperoxides and Carboxylic acids, all contain these carbonyl groups. This class of compounds will typically absorb infared light in the 1740 abs/cm region. By looking at the amplitude of the peak in that wavelength, the extend of oxidation can be determined. Lubes such as Redline and the Series 2000/3000 formulations can generate inaccurate FTIR data, unless the machine has been specifically calibrated with an unused sample of the oil. I speculate what's happening is an ester component of the basestock blend is absorbing light in the 1700-1800 abs/cm range and throwing off the FTIR calibration. The best way to tell if the oxidation # is real is to look at changes in viscosity and TBN. If viscosity is close to the baseline value and the TBN is high, then a high Ox # is mainly calibration error. As an informational note, the by-products of nitration absorb infared light in the 1600-1640 abs/cm range, so the extent of nitration can also be quantified using FTIR. Both oxidation/nitration are "inversely proportional" to TBN, ie as they increase the TBN drops .... TS
 
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