Engines can be expensive, and diesel engines are no exception. Adding an oil additive can help extend the life of your engine, prevent costly repairs, and improve overall performance. Choosing the right one can be tricky with so many options available. In this article, I’ll break down the top diesel engine oil additives to help you make the best choice for your vehicle.
Product Overview / Quick Summary
- Liqui Moly Diesel High Tech Additive: Best overall for cleaning and protection.
- Hot Shot’s Secret Diesel Extreme: Best for extreme cleaning and fuel efficiency.
- Archoil AR9100 Friction Modifier: Best for reducing friction and wear.
- Rev-X Distance+ Oil Additive: Best for high mileage diesel engines.
- Schaeffer Oil 132 Engine Treatment: Best for general engine protection and performance.
Top 5 Best Diesel Engine Oil Additive Reviews
1. Liqui Moly Diesel High Tech Additive
Liqui Moly Diesel High Tech Additive is a well-rounded product designed to clean and protect your diesel engine. It helps remove deposits, improve combustion, and protect against corrosion, leading to smoother engine operation and improved fuel economy. I’ve personally used Liqui Moly products in the past and have always been impressed with their quality.
Pros:
- ✅ Cleans fuel injectors and combustion chamber.
- ✅ Improves fuel economy.
- ✅ Protects against corrosion.
Cons:
- ❌ May not be as potent for extreme cleaning as some other specialized additives.
- ❌ Slightly more expensive than some alternatives.
- ❌ Some users report a mild change in engine sound (though not necessarily negative).
Verdict: A great all-around additive for maintaining a healthy diesel engine. Best for those looking for consistent cleaning and protection without extreme measures.
2. Hot Shot’s Secret Diesel Extreme
Hot Shot’s Secret Diesel Extreme is formulated for deep cleaning and maximum fuel efficiency gains. It uses a concentrated blend of detergents and cetane improvers to remove stubborn deposits, increase cetane levels, and improve overall engine performance. This additive is a bit stronger, so it’s good for engines that need a serious clean.
Pros:
- ✅ Aggressive cleaning action for heavily soiled engines.
- ✅ Noticeable improvement in fuel economy.
- ✅ Helps prevent gelling in cold weather.
Cons:
- ❌ Can be too strong for newer engines or those with sensitive fuel systems.
- ❌ Some users report a slight increase in engine noise after use.
- ❌ Higher price point compared to some other options.
Verdict: Ideal for older diesel engines or those experiencing significant performance issues. Use with caution in newer, more sensitive systems.
3. Archoil AR9100 Friction Modifier
Archoil AR9100 Friction Modifier is designed to reduce friction and wear within the engine. It uses a unique nano-technology to create a protective layer on metal surfaces, minimizing friction and extending engine life. I’ve heard great things about this additive from fellow mechanics, particularly regarding its ability to quiet noisy engines.
Pros:
- ✅ Significantly reduces friction and wear.
- ✅ Can help quiet noisy engines.
- ✅ Improves cold start performance.
Cons:
- ❌ Primarily focuses on friction reduction, not cleaning.
- ❌ Can be expensive compared to other additives.
- ❌ Some users may not notice immediate, dramatic results.
Verdict: Best for those prioritizing engine longevity and friction reduction. A good choice for engines that already run relatively clean but could benefit from added protection.
4. Rev-X Distance+ Oil Additive
Rev-X Distance+ Oil Additive is designed for high-mileage diesel engines. It contains a blend of detergents, seal conditioners, and friction modifiers to revitalize older engines, reduce oil consumption, and improve overall performance. If you have a truck that’s seen a lot of miles, this could be a good option for you.
Pros:
- ✅ Formulated specifically for high-mileage engines.
- ✅ Helps reduce oil consumption.
- ✅ Conditions seals to prevent leaks.
Cons:
- ❌ May not be as effective on newer engines.
- ❌ Some users report a temporary change in oil pressure.
- ❌ Can be more expensive than standard oil additives.
Verdict: Perfect for older diesel engines with high mileage. It’s designed to address common issues in older engines, like oil leaks and excessive consumption.
5. Schaeffer Oil 132 Engine Treatment
Schaeffer Oil 132 Engine Treatment is a versatile additive that enhances engine protection and performance. It reduces friction, wear, and heat, leading to smoother operation and extended engine life. It’s a solid all-around choice for those looking for a reliable additive without specific needs.
Pros:
- ✅ Provides comprehensive engine protection.
- ✅ Improves fuel economy and power.
- ✅ Reduces engine wear and extends engine life.
Cons:
- ❌ Might not offer the same level of specialized cleaning as other dedicated additives.
- ❌ Some users report that the benefits are more subtle than with other additives.
- ❌ Availability can be limited depending on your location.
Verdict: A great choice for those seeking general engine protection and improved performance. Best for drivers who want a reliable additive without focusing on specific issues.
Buying Guide
Choosing the right diesel engine oil additive depends on your engine’s specific needs and your driving habits. Here are some factors to consider:
- Engine Age and Mileage: Older, high-mileage engines often benefit from additives that address wear, leaks, and oil consumption. Newer engines may only need additives for cleaning and protection.
- Driving Conditions: If you frequently tow heavy loads or drive in extreme temperatures, you may need an additive that provides extra protection against heat and wear.
- Specific Concerns: Are you experiencing rough idling, poor fuel economy, or excessive engine noise? Choose an additive that targets these specific issues.
- Additive Type: Consider whether you need a cleaner, friction modifier, seal conditioner, or a multi-purpose additive.
- Reviews and Research: Read reviews and compare products to find the best option for your needs.
FAQs
Q: How often should I use a diesel engine oil additive?
A: It depends on the additive and your driving conditions. Some additives are designed for every oil change, while others are used less frequently. Always follow the manufacturer’s instructions.
Q: Can diesel engine oil additives damage my engine?
A: If used correctly, most additives are safe. However, using the wrong additive or exceeding the recommended dosage can potentially cause problems. Always read the instructions carefully.
Q: Are diesel engine oil additives worth the cost?
A: It depends on your situation. If you’re experiencing specific engine problems or want to extend the life of your engine, a good additive can be a worthwhile investment. If your engine is running well, you may not need one.
Q: Can I mix different types of diesel engine oil additives?
A: It’s generally not recommended to mix different additives unless the manufacturers specifically state that it’s safe to do so. Mixing additives can sometimes lead to unintended chemical reactions.
Q: Where can I buy diesel engine oil additives?
A: You can find them at most auto parts stores, online retailers, and some gas stations.
Conclusion
Choosing the right diesel engine oil additive can significantly improve your engine’s performance and longevity. Whether you’re looking for a powerful cleaner, a friction reducer, or an all-around protector, there’s an additive out there for you. Consider your engine’s needs and driving habits to make the best choice. Hopefully, this review has helped you narrow down the options and find the perfect additive for your diesel engine.
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