The recent increase in excessive camshaft and lifter wear after extended service has shown that some SE-quality engine oils do not provide adequate protection.To determine the effects of oil additives on wear, controlled tests were run using 1972-1974 model cars, unleaded gasoline, and either SE commercial products or experimental formulations. Field experience with 1970-1975 model trucks, leaded gasoline, and SE/CC or SE/CD oils was also investigated.With some commercial oils, in both controlled tests and field experience, excessive wear sometimes occurred after extended service, even with recommended oil-change intervals. Generally, protection from excessive wear was best provided by those oils containing pre-dominantly alkyl ZDP (zinc dithiophosphate) antiwear additive instead of aryl ZDP. These results show that a laboratory engine test is needed to evaluate the long-term wear protection of engine oils.
Cam and Lifter Wear as Affected by Engine Oil ZDP Concentration and Type
Sae Technical Papers
1977 International Automotive Engineering Congress and Exposition ; 1977
1977-02-01
Conference paper
English
Cam and lifter wear as affected by engine oil ZDP concentration and type
Automotive engineering | 1977
|Oil Filtration and Lifter Wear
SAE Technical Papers | 1965
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