Zerex G40 Antifreeze/Coolant Concentrate 1 Gal — Phosphate & Nitrite Free Si‑OAT Protection

Zerex G40 is a premium Si‑Organic Acid Technology (Si‑OAT) antifreeze/coolant concentrate designed to protect modern engines from corrosion, freezing and boiling when mixed to the recommended ratios.

Engine cooling systems depend on the right coolant chemistry. Zerex G40 from Valvoline is an OEM‑approved, phosphate‑ and nitrite‑free ethylene glycol concentrate formulated for cars and light trucks, especially European makes such as BMW, Mercedes‑Benz, Porsche and VW. Its long‑life carboxylate formulation resists corrosion, scale and deposits while remaining safe for aluminum and other metals commonly used in modern cooling systems.

How does Zerex G40 protect my engine from corrosion and deposits?

G40 uses Si‑Organic Acid Technology that buffers and passivates metal surfaces to slow corrosion on aluminum, iron and other metals. The formula is free of nitrites, amines and phosphates, reducing the chance of harmful deposits and keeping radiator passages clear for efficient heat transfer.

• Si‑OAT chemistry targets metal protection without forming harmful sludge.
• Inhibitors guard water pumps, radiators and hoses from rust and scale.
• Batch‑tested additives maintain long service life and system cleanliness.

What mixing ratios and temperature protection does the concentrate offer?

Zerex G40 is a concentrate that must be mixed with clean tap or demineralized water. Different mix ratios deliver predictable freeze and boil protection so you can tailor protection to your local climate and vehicle needs.

• 50/50 mix protects from about −34°F to 265°F and is common for most climates.
• 60/40 mix extends low‑temperature protection to roughly −62°F and higher boil resistance.
• 70/30 mix is for extreme cold, offering protection down to approximately −84°F while maintaining high‑temperature stability.

Is Zerex G40 compatible with my vehicle and cooling system components?

G40 is formulated for modern passenger cars and light trucks and is recommended by OEMs for many European brands. It is compatible with gaskets, hoses and plastics used in cooling systems and avoids common ingredients that can harm seals or paints.

• OEM‑approved for BMW, Mercedes‑Benz, Porsche and VW; suitable for older Audi and Volvo models.
• No imidazole, borates or nitrates, and free of nitrite, amine and phosphate chemistries.
• Safe for rubber, plastic and metal cooling system parts when mixed and used per instructions.

What performance guarantees and safety features should I expect?

Besides industry‑leading freeze and boil protection, Zerex G40 comes with a long‑life warranty and includes safety additives to discourage accidental ingestion. It is both lab batch‑tested and fleet‑tested to ensure consistent performance across applications.

• 5 year / 150,000 mile protection against engine failure from freeze‑ups or boil‑overs.
• Contains 30–50 ppm denatonium benzoate as a bittering agent to deter ingestion.
• High‑quality additives protect against leaks and won’t damage gaskets or hoses.

Who is this for: Zerex G40 concentrate is aimed at car and light‑truck owners, fleet managers, and technicians who need a long‑life, OEM‑approved coolant for European and mixed‑fleet vehicles. Choose G40 when you want robust aluminum protection, long service intervals, and proven freeze/boil performance—whether topping off a radiator or completing a coolant flush.