Pennzoil (550034991-6PK) SAE 30 Motor Oil - 1 Quart, (Pack of 6) SAE 30 grade oil is suitable for use in hydraulic systems, air compressors and industrial circulating systems requiring the use of detergent type single grade motor oils Cleans out up to 40 percent of engine sludge in the first oil change; continues to clean in the second oil change also Helps clean up engines by gently lifting sludge deposits off engine surfaces and dissolving them safely into the oil Controls high-temperature oxidation and deposits