Understanding SOS Service Tests - PEHP7076-02

S·O·S Oil Condition AnalysisMaximize performance byknowing your oil conditionOxygen exposure, heat and contaminantscause all oils to degrade. Engine oil isparticularly susceptible to degradation bysulfur, nitration, by-products of combustion,high temperatures, and water from thecombustion process or condensation. OilCondition Analysis, part of the comprehensiveS·O·S Services program, helps preventcomponent damage by monitoring your oiland keeping track of its degradation. OilCondition Analysis also allowsyou to correct problems that affect oilperformance. The bottom-line benefit:maximum oil performance, optimum oilchange intervals and reduced repair costs.Understanding OilCondition AnalysisOil Condition Analysis is similar to WearRate Analysis with one important exception:It evaluates chemical compounds in the oilrather than wear element particles.Oil Condition Analysis is important foroil from all systems: transmissions andhydraulics, as well as engines.It works like this:1 You submit a sample of new oil, called“reference oil,” when you enroll in theS·O·S Services program and when youget new shipments of bulk oil. Referenceoil samples are processed at no cost toyou. If you are using Cat oil, new oilsamples may not be necessary. Adviseyour S·O·S analyst of the viscosity of theCat oil you use in each system; it has itsown Cat oil reference samples.2 The new oil is scanned by a specialinstrument using infrared light. Informationis stored in the instrument’s memory.3 At each scheduled interval, you submita sample of used oil.4 The Oil Condition Analysis instrumentfocuses a beam of light through a filmof used oil and records the data.5 The instrument uses a mathematicalformula to compare the used and newoils and quantify any differences.Fourier TransformInfrared AnalysisS·O·S Oil Condition Analysis includesan infrared instrument that uses amathematical method to convert rawinstrument data into meaningful terms.This test, often called FT-IR (FourierTransform Infrared Analysis), identifiesand quantifies organic compound groupsby measuring their infrared absorptionat the specific wavelength of each group.Besides identifying oxidation, soot, sulfurproducts and nitration, the test is alsoused to scan for oil contamination byfuel, water or glycol (engine coolant).