Sparex source: https://us.sparex.com/15w-40-heavy-duty-diesel-engine-oil-55-gallons-129533.html Product: 15w-40 Heavy Duty Diesel Engine Oil - 55 Gallons - Sparex S.129533 SKU: S.129533 Listing note: API Service Rating CK-4, Great wear protection for long engine life. API CK-4, CJ-4, CI-4 PLUS, CI-4, and CH Detail enrichment pending: OEM cross references, fitment, catalog pages, and full specifications.