THIS paper describes the background, operation, and results of a series of 50,000-milelow-duty service tests on motor oils. Comparisons of engine cleanliness and wear are presented in oils ranging from base oil to Series 2 level, using several different additive types, and a common base oil.
Large differences were found in the ability of additive types and concentrations to combat harmful low-temperature engine sludge.
Some observations are made on the correlation between full-scale laboratory engine tests and results of this field test.