Product Overview

Liqui Moly MoS2 Anti-Friction Engine Treatment is a well-established oil additive manufactured by Liqui Moly, a German company recognized for its advanced automotive lubricants and engine care products. This engine treatment is designed for use in both gasoline and diesel engines and can be added directly to all types of engine oils—including mineral, semi-synthetic, and fully synthetic oils. The primary function is to reduce friction within the engine by forming a protective molybdenum disulfide (MoS2) layer on metal surfaces, thereby minimizing wear and enhancing engine longevity. Liqui Moly claims the product can lower engine wear by up to 50%, reduce fuel and oil consumption, improve cold-start lubrication, and extend the overall service life of engine components. The treatment is particularly recommended for older engines or vehicles operating under high-stress or high-heat conditions, such as classic cars or performance vehicles. Liqui Moly MoS2 Anti-Friction Engine Treatment falls into the mid-range price category, typically retailing between $10 and $20 for a 300 mL can, which is sufficient for engines with up to 6 liters of oil capacity.

Detailed Assessment

Functionality & Benefits

Rating: 4.5/5 – Liqui Moly MoS2 Anti-Friction Engine Treatment demonstrably reduces friction by creating a lubricating layer of molybdenum disulfide on engine surfaces. This leads to measurable decreases in engine wear, smoother operation, and improved cold-start protection. Many users, especially those maintaining older or high-mileage vehicles, report quieter engine performance and a modest improvement in fuel consumption. However, effects may be less pronounced in modern engines already designed with low-friction technologies.

Technology & Innovation

Rating: 4/5 – The product leverages a proven technology: suspending micronized molybdenum disulfide in oil to create a lasting, low-friction film on metal surfaces. While MoS2 itself is a long-standing solid lubricant, Liqui Moly’s specific colloidal suspension process ensures stable dispersion and compatibility with contemporary engine oils. This technology is reliable, though not as novel as some synthetic or ceramic-based alternatives on the market.

Ease of Use

Rating: 5/5 – Application is straightforward: users simply pour the recommended amount (5% by volume, or 50 mL per liter of oil) directly into the engine oil at any time—no special tools or procedures required. The product is fully miscible with all commercially available oils, reducing the risk of compatibility issues. One 300 mL can treats up to 6 liters of oil, making dosing simple even for non-specialists.

Market Popularity

Rating: 4/5 – Liqui Moly MoS2 enjoys solid popularity globally, particularly among European car owners, classic vehicle enthusiasts, and professional mechanics dealing with older engines. It is a staple in many enthusiast forums and is widely available through automotive retailers. While not quite as prevalent as some competitor brands in North America, its adoption is broad and steadily growing.

Customer Satisfaction

Rating: 4/5 – Feedback from verified customers is predominantly positive. Users often report smoother engine performance, reduced mechanical noise, and perceived improvements in engine longevity. Some skepticism persists in forums regarding its efficacy in modern, tight-tolerance engines or vehicles where oil formulations already integrate advanced friction modifiers. Complaints are rare but typically relate to negligible perceived benefits in newer engines.

Competitive Comparison

Rating: 3.5/5 – Against direct competitors, such as STP Oil Treatment and Liqui Moly Cera Tec, MoS2 stands out for its strong track record in older engines and its colloidal mineral oil delivery system. While Cera Tec offers a ceramic-based approach, reportedly forming a longer-lasting protective layer, MoS2 is favored for its proven, immediate anti-wear benefits and value. Conversely, modern synthetic friction modifiers (e.g., those in Mobil 1 or Castrol Edge) may offer better synergy with the latest OEM oil and engine designs.

Performance Results

Rating: 4/5 – Independent and user-conducted tests confirm modest but consistent reductions in engine friction, wear, and mechanical noise. In controlled environments, slight increases in fuel efficiency and cold-start protection have been observed. However, the scale of improvement may not be dramatic, especially in new vehicles with state-of-the-art metallurgy and oil. The additive shines most in high-mileage, high-heat, or classically designed engines where mechanical friction is a larger concern.

Value for Money

Rating: 4.5/5 – At roughly $15 for a single dose suitable for most passenger cars, Liqui Moly MoS2 delivers tangible anti-wear benefits and a potential boost in engine longevity that outweigh its modest cost. Comparable treatments often cost more or deliver similar benefits with less supporting history. For owners of older or heavily used vehicles, the product provides an excellent return on investment.

Verdict

Liqui Moly MoS2 Anti-Friction Engine Treatment is a well-engineered, trustworthy oil additive with a long history of real-world and laboratory-proven results. Its strongest attributes include a significant reduction in friction and wear, straightforward application, and an attractive price point. The molybdenum disulfide technology is not revolutionary but remains highly effective, especially for classic vehicles, high-mileage engines, or cars regularly subjected to high-stress conditions. In newer engines, the benefit may be less pronounced due to advanced factory oil formulations and tighter engineering tolerances, but the product remains fully compatible and harmless when used as directed. Its biggest weakness is that improvements in engine smoothness and fuel economy may not be dramatic or immediately noticeable for every driver, particularly in modern vehicles already optimized for low friction. The ideal candidates for this treatment are owners of classic cars, high-mileage daily drivers, and those operating under severe service conditions or in hot climates. Given its proven effectiveness, excellent ease of use, and strong value proposition, Liqui Moly MoS2 Anti-Friction Engine Treatment comes highly recommended for its target use cases and earns an overall rating of 4.5 out of 5 stars.