GB12981-2025
Motor vehicle brake fluids
机动车辆制动液
GB 12981-2025 is an upcoming mandatory Chinese national standard for Motor vehicle brake fluids. It appears in the Auto compliance cluster with a energy efficiency focus and has an implementation date of Jan 1, 2027.
Applicability depends on product scope, certification route, competent authority notices and transition rules. Requst for the translation or verify source before using this record in a compliance decision.
Compliance overview
Scope and applicability
This standard applies to non-petroleum-based motor vehicle brake fluids used in hydraulic braking and hydraulic clutch systems. It is specifically designed for fluids formulated from alcohols, alcohol ethers, and their synthetics, intended to contact sealing components primarily made of SBR (styrene-butadiene rubber) or EPDM (ethylene propylene diene monomer). It does not apply to petroleum-based brake fluids. The products are classified into five viscosity and temperature grades: HZY3, HZY4, HZY5, HZY6, and the newly introduced HZY7.
Technical requirements
The standard specifies comprehensive physical and chemical property requirements for brake fluids across all grades. Key parameters include high-temperature performance (Equilibrium Reflux Boiling Point and Wet Equilibrium Reflux Boiling Point), which dictate the fluid's resistance to vapor lock. It also sets strict limits on kinematic viscosity at extreme temperatures (-40°C and 100°C) to ensure proper fluid flow in varying climates. Additionally, the standard mandates criteria for liquid stability (both high-temperature and chemical stability) and pH value to ensure the fluid's chemical integrity over time. A newly added requirement for reserve alkalinity is now applicable across all grades. Furthermore, the standard outlines rigorous limits for corrosion resistance (evaluating mass changes in metals like tinned iron, steel, aluminum, and cast iron) and rubber compatibility. Manufacturers must ensure the fluid does not cause excessive swelling, hardness loss, or carbon black extraction in SBR and EPDM rubber components.
Testing methods
The standard mandates a series of rigorous laboratory evaluations to verify compliance. Key testing procedures include: Evaporation performance testing (evaluating mass loss and residue pour point), pH value determination via a composite electrode, and liquid stability assessment under high-temperature and chemical mixing conditions. It also specifies a metal coupon corrosion test using a multi-metal stack (tinned iron, steel, aluminum, cast iron, brass, copper, zinc) immersed in moisture-contaminated brake fluid. Low-temperature flowability and appearance tests are conducted at -40°C and -50°C. Finally, the standard includes water tolerance and fluid compatibility tests, an oxidation resistance test, and a rubber compatibility test using SBR cups and EPDM samples. Disputes in testing results are resolved using specifically designated reference methods.
FAQs
What products are regulated under GB 12981-2025?
This standard regulates non-petroleum-based motor vehicle brake fluids used in hydraulic braking and hydraulic clutch systems. It applies to products based on alcohols, alcohol ethers, and their synthetics, designed to contact SBR or EPDM rubber seals.
Are there any major updates in GB 12981-2025 compared to the 2012 version?
The 2025 revision introduces the new HZY7 grade, adds a reserve alkalinity requirement for HZY3-HZY6, updates the testing method for wet equilibrium reflux boiling point, and removes the "rust prevention" and "stroke simulation performance" requirements found in the 2012 version.
How do the HZY grades in GB 12981-2025 compare to international DOT or ISO standards?
The Chinese HZY grades correspond directly to ISO 4925:2020 classes. Specifically, HZY3, HZY4, and HZY5 align with the US Department of Transportation's DOT3, DOT4, and DOT5.1 specifications, while HZY6 and HZY7 correspond to ISO Class 6 and Class 7 respectively.
The summary above provides a high-level overview of GB 12981-2025. To ensure complete compliance for your products entering the Chinese market, a precise and professional translation of the full technical specifications is essential. Purchase our high-quality English translation of GB 12981-2025 today to access all detailed parameters, tables, and testing procedures.
Applicability hints
- Type
- Product
- CCS
- E39
- ICS
- 75.120
- Competent department
- National Energy Administration
- Technical committee
- National Technical Committee on Petroleum Products and Lubricants of Standardization Administration of China
Relationships
Replaces:GB 12981-2012 (Current)