API CJ-4 Diesel Engine Oils API CJ-4 diesel engine oils are a type of engine oil that meets the performance requirements set by the American Petroleum Institute (API) for heavy-duty diesel engines. CJ-4 oils are specifically designed to provide enhanced protection for engines equipped with exhaust after-treatment systems, such as diesel particulate filters (DPF) and diesel oxidation catalysts (DOC). CJ-4 oils are formulated to provide improved wear protection, better oxidation stability, and reduced emissions compared to previous API oil categories. They are designed to meet the demands of modern diesel engines, which operate at higher temperatures and pressures, and have stricter emissions regulations. Some key features and benefits of API CJ-4 diesel engine oils include: 1. Enhanced wear protection: CJ-4 oils are formulated with advanced additives that provide superior protection against wear, helping to extend the life of engine components. 2. Improved oxidation stabil…