Dot 4 Mineral Oil: What You Need to Know

Dot 4 mineral oil is a standard lubricant grade widely used in older passenger vehicles and light-duty engines. Understanding its properties helps ensure reliable engine protection and performance. This guide covers everything from viscosity ratings to real-world applications, helping you choose the right oil for your car.

What Is Dot 4 Mineral Oil?

Dot 4 mineral oil is classified as a multi-grade lubricant with a minimum viscosity of 46 mm²/s at 100°C and 28 mm²/s at 0°C. It’s a non-synthetic blend designed for standard combustion engines, offering balanced protection in moderate climates and typical driving conditions. Unlike synthetic oils, dot 4 mineral oil relies on refined base oils and viscosity modifiers to maintain stability under heat and cold.

Key Specifications and Performance

• Viscosity: ⁴⁶⁄₂₈ (ISO VG ⁴⁶⁄₂₈), ideal for vehicles with engine designs calibrated for this grade.
  
• Pour Point: -26°C, ensuring flow in cold climates without thickening.
  
• Thermal Stability: Maintains lubricity up to 220°C, reducing wear during high-load operation.
  
• Additives: Contains anti-wear agents, detergents, and antioxidants to prevent sludge and corrosion.
  

When to Use Dot 4 Mineral Oil

Dot 4 mineral oil is best suited for vehicles manufactured between 2000 and 2015, particularly those with naturally aspirated engines. It’s commonly used in:

• Older sedans and hatchbacks
  
• Light trucks and SUVs with 4-cylinder engines
  
• Classic cars requiring original equipment lubricants
  

Avoid dot 4 in high-performance or modern engines with turbo-charging, as newer synthetics offer better protection under extreme conditions. Always check your owner’s manual or oil cap for manufacturer recommendations.

Dot 4 vs Other Grades: What’s the Difference?

Dot 4 sits between dot 2 and dot 5 mineral oils. While dot 2 offers lower cold-flow performance, dot 4 provides stronger high-temperature stability. Compared to dot 5, dot 4 is lighter and less expensive but lacks the extended protection for engines under sustained high heat. For most everyday use, dot 4 delivers reliable performance without over-specifying.

Benefits and Practical Tips

Using dot 4 mineral oil supports engine longevity by reducing friction and heat buildup. Benefits include:

• Cost-effective maintenance for older vehicles
  
• Compatibility with standard engine seals and gaskets
  
• Widespread availability at auto parts stores and service centers
  

To maximize performance:

• Change oil every 10,000–15,000 km or as per manufacturer schedule
  
• Use only oils labeled as mineral or dot 4 to avoid chemical incompatibility
  
• Store oil in sealed containers away from direct sunlight and extreme temperatures

Common Myths About Dot 4 Mineral Oil

1. Myth: Dot 4 is obsolete and useless today.
   Reality: While synthetics dominate, dot 4 remains effective for vehicles built around 2000–2015.
   
2. Myth: Any mineral oil works if it’s dot 4 labeled.
   Reality: Only oils meeting ISO 32 specifications guarantee proper viscosity and protection.
   
3. Myth: Higher viscosity dot 4 oils perform better.
   Reality: Stick to ⁴⁶⁄₂₈ grade—higher numbers reduce fuel efficiency without added benefit.

Conclusion

Dot 4 mineral oil continues to serve as a dependable, affordable choice for many vehicles built in its target era. By understanding its specs and limitations, you ensure proper engine care and avoid unnecessary expenses. Always verify your vehicle’s requirements and maintain regular oil changes to keep your engine running smoothly. If in doubt, consult your manual or a trusted mechanic before switching oils.

For safe driving, trust the proven performance of dot 4 mineral oil when your car needs it—consistently and correctly.