Sierra Antifreeze & Accessories

Sierra Antifreeze & Accessories: Safer Cooling System Protection

When it comes to protecting an engine's cooling system without the toxicity risks of conventional antifreeze, Sierra stands in a category of its own. As a brand under the PEAK family — widely recognized as the pioneer and market leader in the safer propylene glycol (PG) antifreeze category — Sierra has built its reputation on one foundational difference: choosing propylene glycol over ethylene glycol as its base chemistry.

Antifreeze and coolant accessories from Sierra are formulated with PG rather than ethylene glycol, the base for traditional antifreeze. Because of its PG formula, Sierra antifreeze is less toxic and therefore safer for people, pets, and wildlife than conventional antifreeze — a meaningful advantage for households with children or animals, and for environmentally sensitive applications like marine or outdoor use.

What Sets Sierra Antifreeze Apart

Sierra's propylene glycol antifreeze isn't just a "safer" alternative that compromises on performance. It delivers excellent engine protection against freeze-up, boil-over, and corrosion, while maintaining critical heat transfer properties throughout the cooling system. Sierra antifreeze demonstrates outstanding corrosion prevention performance in all standard industry tests, meeting the requirements of ASTM D5216 (Propylene Glycol Base Engine Coolant) as well as the corrosion prevention requirements of ASTM D3306, ASTM D4985, and GM specifications including ASTM D2809 for cavitation erosion corrosion on aluminum pumps.

For marine applications, Sierra also produces a Synthetic Blend Antifreeze line that features a high-tech poly-organic POAT (Poly Organic Acid Technology) formula combined with a unique additive package. This formula helps engines maintain optimum operating temperatures, seals pinhole leaks and fissures, and offers excellent metal and cavitation protection. It is designed to protect gas engines for up to 4,000 hours or 2 years, and diesel engines for an impressive 12,500 hours or 7 years.

Key Features of Sierra Antifreeze & Coolant

• Propylene Glycol (PG) Base: Less toxic than traditional ethylene glycol antifreeze — safer for people, pets, and the surrounding environment
• Freeze & Boil-Over Protection: Guards against extreme temperature conditions in all seasons
• Corrosion Inhibitors: Protects aluminum, copper, brass, and cast iron engine components from rust, scale, and corrosion
• ASTM Compliance: Meets or exceeds multiple industry standards including ASTM D5216, D3306, D4985, and GM corrosion specs
• Marine-Grade Options: Synthetic Blend formulas engineered specifically for water-cooled inboard, outboard, and stern-drive engines
• Extended Service Life: POAT formula synthetic blends offer long-interval protection measured in thousands of engine hours
• Broad Compatibility: Compatible with all other coolants and suitable for both gasoline and diesel engines

The Right Antifreeze for Environmentally Sensitive Applications

Sierra's propylene glycol antifreeze is a natural fit wherever coolant spills or leaks could pose a risk to animals or the environment — whether that's a family garage, a farm, a marina, or a boat. The same chemistry trusted in food-processing and pharmaceutical industries underlies Sierra's commitment to a safer antifreeze that doesn't cut corners on engine protection. Whether you're maintaining a daily driver, a diesel workhorse, or a marine engine, Sierra's antifreeze and accessories deliver the year-round performance your cooling system demands.