Quicksilver MerCruiser High-Performance Oil Filter 858004Q for 4.5L & 6.2L Engines — Synthetic Media, Anti-Drain Valve

The Quicksilver 858004Q is a high-performance replacement oil filter designed specifically for MerCruiser sterndrive and compatible inboard engines, delivering improved contaminant removal and reliable start-up lubrication.

Built to meet Mercury Marine original equipment specifications, this Quicksilver oil filter is engineered for marine duty where salt, vibration and heavy engine loads demand robust filtration. It replaces the factory element on many General Motors-built MerCruiser sterndrive and inboard engines (and fits Mercury Marine 4.5L and 6.2L units), providing a durable, corrosion-resistant housing and advanced synthetic filter media for cleaner oil and longer engine life.

How does this filter improve oil cleanliness on a boat engine?

The 858004Q uses a superior synthetic filter media designed to trap and hold a very high percentage of particulates, helping keep oil passages and bearings cleaner between service intervals. Cleaner oil reduces wear from abrasive contaminants and supports consistent oil pressure under load.

• High-efficiency synthetic media that removes up to 97% of oil contaminants
• Deep-pleat construction to increase dirt-holding capacity
• Stable performance in marine temperature and vibration conditions

Will this filter prevent oil loss and dry starts?

This Quicksilver element includes an anti-drain back valve that holds oil in the filter when the engine is off, ensuring immediate lubrication at start-up and helping avoid metal-to-metal contact during those critical first rotations. It helps protect bearings and cam surfaces by maintaining oil where it's needed before the pump builds full pressure.

• Integrated anti-drain back valve for instant oil supply on start
• Reduces wear during repeated stop/start cycles typical on boats
• Reliable operation across a range of marine mounting angles

How rugged is the filter housing and how does it cope with marine environments?

The 858004Q features a shell that is roughly 50% thicker than conventional filters, finished with corrosion-resistant coating to stand up to saltwater exposure and onboard humidity. The reinforced metal shell resists denting and deformation from impacts and pressure fluctuations common in marine service.

• Thicker metal shell for improved crush resistance
• Corrosion-resistant finish for longer life in wet environments
• Manufactured to Mercury Marine OEM specifications for fit and durability

Which engines and applications are compatible with this Quicksilver filter?

This element is a direct replacement for MerCruiser sterndrive and inboard engines built by General Motors (excluding V6 engines with block-mounted filters) and also fits Mercury Marine 4.5L and 6.2L models. It’s intended for owners seeking an OEM-grade replacement that matches factory performance and service intervals.

• Fits MerCruiser GM-built sterndrive and inboard engines (not V6 block-mounted filters)
• Compatible with Mercury Marine 4.5L and 6.2L engines
• Produced to Mercury Marine OEM standards for proper fit and protection

Who is this for: The Quicksilver 858004Q is aimed at recreational and professional boat owners, marine technicians and fleet operators who need a durable, OEM-quality oil filter for MerCruiser and compatible inboard engines. If you value high contaminant capture, anti-drain protection at startup, and a corrosion-resistant housing matched to factory specifications, this filter is a reliable choice for routine maintenance and extended engine protection.