Description:
OZ 6521 is a minimum treat-rate, cost-effective additive package designed to meet API CD performance standards with a Total Base Number (TBN) of 11. It also meets U.S. military performance requirements for lubricants used in combined engine and gearbox applications.
Engineered for use with Group I mineral base oils, OZ 6521 delivers the high alkalinity necessary to protect diesel engines operating with high-sulfur fuels—particularly those exceeding the 25 ppm sulfur limit common in European fuel standards. The additive is especially suitable for heavy-duty diesel applications, offering both engine protection and gearbox lubrication within a single oil formulation.
Key Features:
Meets API CD and military-grade combined engine/gear oil requirements
Delivers high TBN (11) for effective acid neutralization in high-sulfur fuel environments
Designed for use with traditional Group I base stocks
Provides excellent wear protection, detergency, and oxidation stability
Suitable for combined engine and gear lubrication
Cost-effective solution for low and mid-tier diesel applications
Applications:
Heavy-duty diesel engines in commercial and industrial equipment
Lubrication of combined engine-gear systems
Ideal for older fleets operating in regions with high-sulfur diesel fuel
Suitable for blending monograde and multigrade diesel engine oils
Formulation Guidelines:
Blend with mineral base oil, pour point depressant, and optionally a viscosity modifier for multigrade oils
Follow standard blending procedures for additive incorporation and temperature control
Handling and Safety Considerations:
Avoid contact with water and wet gas during storage and handling
Do not expose to direct air contact when heated, as it may cause discoloration
To prevent ZDDP decomposition, avoid overheating—especially during mixing
Heating above 140°F (60°C) is permitted short-term, but long-term storage should not exceed 100°F (40°C)
Decomposition may release hydrogen sulfide, mercaptans, and olefins, requiring adequate ventilation
Packaging & Storage:
Supplied in 200-liter metal drums, IBC totes, or bulk containers
Store in dry, clean, and well-ventilated warehouses away from direct sunlight and moisture
Handle using standard lubricant additive practices
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