Honda Type 2 coolant is a blue, premixed 50/50 ethylene glycol–based antifreeze that uses borate and phosphate corrosion inhibitors and is silicate-free.
Composition in detail
The coolant is engineered to protect Honda/Acura cooling systems by providing corrosion resistance, freeze protection, and boilover protection. The following elements are typical components of Honda Type 2 formulations, though exact mixes can vary by batch and product line.
The main chemical components are:
- Ethylene glycol-based base fluid: the primary antifreeze component that lowers the freezing point and raises the boiling point of the coolant.
- Deionized water: used to achieve the designed 50/50 premixed ratio and overall coolant properties.
- Silicate-free inorganic corrosion inhibitors: primarily borates and phosphates that protect metals such as aluminum, cast iron, and copper alloys from corrosion.
- Colorant and stabilizers: blue dye and minor additives (e.g., anti-foam agents, rust inhibitors) to maintain performance and visibility.
Note: Honda emphasizes using Genuine Honda Type 2 coolant to ensure compatibility with engine materials and sealing surfaces.
Purpose and compatibility
Type 2 coolant is designed for modern Honda and Acura engines that use mixed-metal cooling systems. It is recommended to use the Type 2 formulation specified by the manufacturer and to avoid mixing with Type 1 or other brands unless explicitly allowed by Honda. If switching coolant types, a complete flush is advised.
Color and packaging details
The official Type 2 coolant is blue in color and is commonly sold in premixed 50/50 bottles or as a concentrate that requires dilution according to Honda's guidelines.
Summary
Honda Type 2 coolant is a blue, silicate-free, ethylene glycol–based antifreeze with borate and phosphate corrosion inhibitors, supplied as a premixed 50/50 formulation. Its composition is designed to protect Honda/Acura cooling systems across metals while providing reliable freezing and boiling protection. Always follow Honda's official guidance and use Genuine Type 2 coolant to ensure compatibility and warranty compliance.