SEAL-U-CUP 8T8387 - Caterpillar

Caterpillar-Built EnginesSome new oil additives are used by several major oil companies in their lubricants. These new additives have copper (Cu) compounds in their formulas which can cause high copper indications during Scheduled Oil Sampling (S.O.S) tests. Copper levels as high as 120 parts per million (ppm) are possible for new oils which use these additives. These oils can also cause high indications when used as make up oil.
These additives also have different mineral contents, such as sodium (Na), which can cause higher-than-normal indications.
For this reason, if the S.O.S. shows higher-than-normal levels of copper or any mineral, get a sample of the oil that has never been used and test it. Dealers must then use test data from the new oil sample to establish new guidelines for future S.O.S. tests on a specific engine.