Malibu M-Series/LT4 Engine Coolant

Sierran Peak Marine Engine Coolant is a premium-grade, propylene glycol-based antifreeze and coolant formulated specifically for marine engines operating in both saltwater and freshwater environments. Utilizing advanced Organic Acid Technology (OAT), it offers extended life corrosion protection without the use of silicates, phosphates, or amines—ensuring compatibility with aluminum, copper, brass, and cast iron engine components. Engineered for optimal thermal stability and environmental safety, Sierran Peak Marine Coolant is non-toxic, biodegradable, and meets or exceeds major OEM marine coolant specifications. It provides excellent protection against freezing, boiling, cavitation, and scale buildup—crucial in high-performance marine applications including inboard/outboard and stern-drive engines.