Purpose and Specifications

LIQUI MOLY DIESEL SYNTHOIL 5W40 is a premium synthetic diesel engine oil designed for modern diesel engines requiring extended protection and performance. This oil meets multiple international standards including ACEA B4, API CF, MB 229.3, BMW LL-98, and VW 505.00, making it suitable for a wide range of diesel vehicles and applications.

The 5W40 viscosity rating means the oil flows easily in cold temperatures (winter protection) while maintaining a protective film at high engine temperatures. This balanced performance works in both cold climates and hot operating conditions, protecting your engine year-round.

Key Benefits:

• Synthetic formulation provides superior engine cleanliness by preventing acid and sludge buildup
• Extended oil change intervals reduce maintenance frequency and costs
• Enhanced wear protection for engine components under stress
• Better fuel economy compared to conventional oils
• Stable performance across extreme temperature ranges

When to Use / Replace?

For normal driving conditions (highway driving, moderate loads, mild weather), you can typically extend oil changes to 10,000 kilometers or 6 months, whichever comes first. Synthetic oils like this one allow longer intervals than conventional oils.

For severe driving conditions (frequent towing, heavy loads, stop-and-go traffic, extreme temperatures, or short trips), change your oil every 5,000 kilometers or 3 months. Severe use breaks down oil faster, so more frequent changes protect your engine.

This oil performs reliably in operating temperatures from -25°C to +40°C, making it suitable for most climates. Store unopened containers in a cool, dry place with a shelf life of approximately 3-5 years.

Frequently Asked Questions

Q: Can I use this oil in my older diesel engine?
A: Check your vehicle's owner manual first. This oil meets VW 505.00 and MB 229.3 standards, so it works well with many European diesel engines. However, some older engines may require different specifications, so verify compatibility before use.

Q: How do I know if my driving is 'severe use'?
A: You're in the severe category if you frequently tow trailers, carry heavy loads, drive in stop-and-go city traffic, idle for long periods, operate in extreme heat or cold, or take many short trips where the engine doesn't fully warm up. If any of these apply, follow the 5,000 km / 3-month change interval.

Q: Is synthetic oil worth the extra cost?
A: Yes. Synthetic oils last longer (allowing extended change intervals), provide better engine protection, improve fuel economy, and reduce overall maintenance costs. For diesel engines under stress, the investment pays for itself through longer engine life and fewer oil changes.