6 Gallons Schaeffer's OTR PLUS Full Synthetic 5W-40 Diesel Engine Oil. Exceeds API Service Categories for heavy-duty-diesel engine oil: CK-4, CJ-4, CI-4, CI-4 Plus and older.SynShield® OTR Plus 5W-40 Engine Oil is a premium advanced performance, fully synthetic, heavy-duty diesel engine oil formulated to provide maximum protection against wear, oxidation, deposit formation, soot contamination and aeration.
