Sierra 18-9400CAT-4 4-Cycle Stern Drive Engine Oil 25W40 FC-W 5 Quart

Sierra 18-9400CAT-4 NMMA FC-W Catalyst Compatible Oil is specifically engineered for modern four-stroke stern drive and inboard marine engines, providing superior protection for engines with or without emission catalyst systems. This premium 25W40 marine oil delivers exceptional performance in the extreme operating conditions common to recreational marine applications.

Key Features:

• Industry-leading wear protection and deposit control for extended engine longevity
• Advanced catalyst-compatible formula prevents phosphorus depletion and extends catalyst life
• Enhanced detergent and dispersant properties suspend contaminants and prevent engine sludge formation
• Minimizes internal engine corrosion in harsh marine environments
• High-quality base stocks resist thermal and oxidative breakdown under extreme heat
• Highly shear-stable viscosity stabilizers prevent excessive oil thinning
• Reduced engine friction for improved efficiency and performance
• Advanced ZDDP anti-wear additive technology with superior thermal stability

This NMMA FC-W certified formula meets the demanding requirements of recreational marine engines that experience high-load operation, extended idle periods, and exposure to moisture. The 5-quart container provides convenient capacity for typical oil changes on stern drive and inboard applications.