Purpose and Specifications

LIQUI MOLY 25031 Marine Gear Oil GL4/GL5 80W-90 is a high-performance transmission oil in a convenient 250ml tube, perfect for manual shift transmissions in boats, vehicles, and marine gear systems. This premium mineral-based oil delivers a stable lubricating film that cuts wear, quiets noisy gears, and shields against corrosion even in harsh saltwater environments. Its 80W-90 viscosity flows smoothly at cold starts down to -12°C and stays thick under high heat up to 130°C, ensuring reliable protection during towing, racing, or heavy loads. Approved for API GL4/GL5 and MT-1 standards, it meets tough manufacturer specs for extended performance without attacking seals.

When to Use / Replace?

Use this oil in high-load manual transmissions, differentials, and marine gearboxes where smooth shifting and maximum durability matter. Ideal for BMW axles, Japanese transmissions, and boats facing extreme conditions. Replace every 60,000 km or 3 years for road vehicles, or annually (every 12 months) for marine use to prevent buildup and maintain peak efficiency. Shelf life is 5 years unopened when stored cool and dry.

• Minimizes friction for effortless gear changes
• Absorbs heat to avoid overheating damage
• Provides outstanding rust protection in wet conditions
• Supports longer intervals between changes, saving time and money

Frequently Asked Questions

Is LIQUI MOLY 25031 safe for my boat's gearbox? Yes, it's specially formulated for marine applications with excellent corrosion resistance and GL4/GL5 approvals, protecting against saltwater damage.

How often should I change this gear oil? For vehicles, every 60,000 km or 3 years; for marine gear, check annually and replace as needed based on usage.

Will it work in cold weather? Absolutely, the 80W rating ensures easy flow at low temps down to -12°C for quick protection on startup.