GB 12981-2025 Motor vehicle brake fluids English
Warning - This product is not considered as a flammable hazardous material. However, it may cause irritation to the eyes and skin. In case of contact, rinse immediately with water. This product erodes paint.
1 Scope
This standard specifies the product variety and labeling, technical requirements, test method, inspection rules and marking, packaging, transportation and storage of non-petroleum-based brake fluids for hydraulic braking and hydraulic clutch systems in motor vehicles.
This document applies to motor vehicle brake fluids manufactured using non-petroleum-based base fluids (alcohols, glycol ethers, and their synthetic compounds) with various additives, designed for contact with sealing elements primarily made from Styrene-Butadiene Rubber (SBR) or Ethylene Propylene Diene Monomer (EPDM).
2 Normative references
The following normative documents contain provisions which, through reference in this text, constitute provisions of this document. For dated references, only the edition cited applies. For undated references, the latest edition (including any amendments) applies.
GB/T 265 Petroleum products - Determination of kinematic viscosity and calculation of dynamic viscosity
GB/T 514 Specification for liquid-in-glass thermometers for testing of petroleum products
GB/T 531.1 Rubber vulcanized or thermoplastic - Determination of indentation hardness - Part 1: Durometer method (Shore hardness)
GB/T 531.2 Rubber vulcanized or thermoplastic - Determination of indentation hardness - Part 2: IRHD pocket meter method
GB/T 2520 Cold-reduced electrolytic tinplate
GB/T 3190 Chemical composition of wrought aluminium and aluminium alloys
GB/T 4756 Method for manual sampling of petroleum liquids
GB/T 5231 Designation and chemical composition of wrought copper and copper alloys
GB/T 8170 Rules of rounding off for numerical values & expression and judgment of limiting values
GB/T 8926 Standard test method for insolubles in used lubricating oils
GB/ T9439 Grey iron castings
GB/T 11158-2008 Specifications for high temperature test chambers
GB/T 13818 Die casting zinc alloys
GB/T 37285 Reference fluids for compatibility testing of motor vehicle braking fluids
NB/SH/T 0164 Petroleum and related products packaging, storage, transportation and acceptance of delivery rules
NB/SH/T 0430 Standard test method for determination of equilibrium reflux boiling point of motor vehicle brake fluid
SH/T 0091 Determination of reserve basicity of engine coolant and rust agent
3 Terms and definitions
No terms and definitions are listed in this document.
4 Product variety and marking
4.1 Product variety
This document covers the product series of non-petroleum-based brake fluids for hydraulic braking and hydraulic clutch systems in motor vehicles. The product series designation is HZY, where the three uppercase letters H, Z, and Y are the first letters of Pinyin for the three Chinese terms "He Cheng" (synthetic), "Zhi Dong" (brake), and "Ye Ti" (fluid), respectively. Based on different operating temperature and viscosity requirements, the products are classified into five grades: HZY3, HZY4, HZY5, HZY6, and HZY7. These correspond respectively to Class 3, Class 4, Class 5.1, Class 6, and Class 7 in ISO 4925:2020. Among them, HZY3, HZY4, and HZY5 correspond to the brake fluid types of U.S. Department of Transportation, i.e. DOT3, DOT4 and DOT5.1.
4.2 Product marking
The marking on brake fluid products shall at least indicate: Product grade motor vehicle brake fluid
Example: HZY3 motor vehicle brake fluid
5 Technical requirements and test methods
The technical requirements and test methods for motor vehicle brake fluids shall meet those specified in Table 1.
6 Inspection rules
6.1 Inspection classification and items
6.1.1 Factory inspection
6.1.3 Factory inspection includes batch inspection and periodic inspection.
Batch inspection items include: appearance, kinematic viscosity, equilibrium reflux boiling point, wet equilibrium reflux boiling point, and pH value.
Periodic inspection items include: evaporation performance (HZY3 and HZY4), reserve alkalinity, corrosivity, and rubber compatibility. Periodic inspection shall be conducted once per month.
6.1.2 Type inspection
6.2.1 Type inspection items include all technical requirements specified in Clause 5. Type inspection is usually conducted once every two years, but where the production process is not changed, it may be conducted once every four years.
Type inspection shall be carried out under any of the following conditions:
a) release or type appraisal and approval of new products;
b) changes of the production line or production site;
b) significant change in raw material, production process or operating procedures after the production is started, which may affect the product’s performance;
d) where the production is resumed after production halt for at least one year;
e) where there is significant difference between the result of factory inspection and that of previous type inspection, and the factors causing the difference cannot be determined or their impact on product performance is unclear;
f) where type inspection is required by the national quality supervision organization;
g) where the user has specific requirements.
6.2 Batching
Under the condition that the raw materials and production process are not changed, the products of a tank or a kettle are considered as a batch.
6.3 Sampling
It shall be conducted in accordance with GB/T 4756. 4L samples shall be taken from each batch for inspection and reservation.
6.4 Judgment rules
The factory inspection and type inspection results shall be rounded off according to GB/T 8170, if the results conform to the technical requirements specified in Clause 5, the products shall be considered as acceptable.
6.5 Re-inspection rules
If any result of factory inspection or type inspection fails to meet the technical requirements of Clause 5, double amount of samples shall be taken and the unacceptable product shall be re-inspected according to the requirements of GB/T 4756. If any the re-inspection result still fails to meet the technical requirements, this batch of products shall be considered as unacceptable.
Contents
Foreword Ⅲ
1 Scope
2 Normative references
3 Terms and definitions
4 Product variety and marking
5 Technical requirements and test methods
6 Inspection rules
7 Marking, packaging, transportation and storage
Annex A (Normative) Test method for evaporation performance of brake fluid
Annex B (Normative) Determination of pH value of brake fluid
Annex C (Normative) Test method for liquid stability of brake fluid
Annex D (Normative) Test method for corrosion of metal laminates by brake fluid
Annex E (Normative) Test method for low-temperature fluidity and appearance of brake fluid
Annex F (Normative) Test method for water insolubility and compatibility of brake fluid
Annex G (Normative) Test method for oxidation resistance of brake fluid
Annex H (Normative) Test method for rubber compatibility of brake fluid
GB 12981-2025 Motor vehicle brake fluids English
Warning - This product is not considered as a flammable hazardous material. However, it may cause irritation to the eyes and skin. In case of contact, rinse immediately with water. This product erodes paint.
1 Scope
This standard specifies the product variety and labeling, technical requirements, test method, inspection rules and marking, packaging, transportation and storage of non-petroleum-based brake fluids for hydraulic braking and hydraulic clutch systems in motor vehicles.
This document applies to motor vehicle brake fluids manufactured using non-petroleum-based base fluids (alcohols, glycol ethers, and their synthetic compounds) with various additives, designed for contact with sealing elements primarily made from Styrene-Butadiene Rubber (SBR) or Ethylene Propylene Diene Monomer (EPDM).
2 Normative references
The following normative documents contain provisions which, through reference in this text, constitute provisions of this document. For dated references, only the edition cited applies. For undated references, the latest edition (including any amendments) applies.
GB/T 265 Petroleum products - Determination of kinematic viscosity and calculation of dynamic viscosity
GB/T 514 Specification for liquid-in-glass thermometers for testing of petroleum products
GB/T 531.1 Rubber vulcanized or thermoplastic - Determination of indentation hardness - Part 1: Durometer method (Shore hardness)
GB/T 531.2 Rubber vulcanized or thermoplastic - Determination of indentation hardness - Part 2: IRHD pocket meter method
GB/T 2520 Cold-reduced electrolytic tinplate
GB/T 3190 Chemical composition of wrought aluminium and aluminium alloys
GB/T 4756 Method for manual sampling of petroleum liquids
GB/T 5231 Designation and chemical composition of wrought copper and copper alloys
GB/T 8170 Rules of rounding off for numerical values & expression and judgment of limiting values
GB/T 8926 Standard test method for insolubles in used lubricating oils
GB/ T9439 Grey iron castings
GB/T 11158-2008 Specifications for high temperature test chambers
GB/T 13818 Die casting zinc alloys
GB/T 37285 Reference fluids for compatibility testing of motor vehicle braking fluids
NB/SH/T 0164 Petroleum and related products packaging, storage, transportation and acceptance of delivery rules
NB/SH/T 0430 Standard test method for determination of equilibrium reflux boiling point of motor vehicle brake fluid
SH/T 0091 Determination of reserve basicity of engine coolant and rust agent
3 Terms and definitions
No terms and definitions are listed in this document.
4 Product variety and marking
4.1 Product variety
This document covers the product series of non-petroleum-based brake fluids for hydraulic braking and hydraulic clutch systems in motor vehicles. The product series designation is HZY, where the three uppercase letters H, Z, and Y are the first letters of Pinyin for the three Chinese terms "He Cheng" (synthetic), "Zhi Dong" (brake), and "Ye Ti" (fluid), respectively. Based on different operating temperature and viscosity requirements, the products are classified into five grades: HZY3, HZY4, HZY5, HZY6, and HZY7. These correspond respectively to Class 3, Class 4, Class 5.1, Class 6, and Class 7 in ISO 4925:2020. Among them, HZY3, HZY4, and HZY5 correspond to the brake fluid types of U.S. Department of Transportation, i.e. DOT3, DOT4 and DOT5.1.
4.2 Product marking
The marking on brake fluid products shall at least indicate: Product grade motor vehicle brake fluid
Example: HZY3 motor vehicle brake fluid
5 Technical requirements and test methods
The technical requirements and test methods for motor vehicle brake fluids shall meet those specified in Table 1.
6 Inspection rules
6.1 Inspection classification and items
6.1.1 Factory inspection
6.1.3 Factory inspection includes batch inspection and periodic inspection.
Batch inspection items include: appearance, kinematic viscosity, equilibrium reflux boiling point, wet equilibrium reflux boiling point, and pH value.
Periodic inspection items include: evaporation performance (HZY3 and HZY4), reserve alkalinity, corrosivity, and rubber compatibility. Periodic inspection shall be conducted once per month.
6.1.2 Type inspection
6.2.1 Type inspection items include all technical requirements specified in Clause 5. Type inspection is usually conducted once every two years, but where the production process is not changed, it may be conducted once every four years.
Type inspection shall be carried out under any of the following conditions:
a) release or type appraisal and approval of new products;
b) changes of the production line or production site;
b) significant change in raw material, production process or operating procedures after the production is started, which may affect the product’s performance;
d) where the production is resumed after production halt for at least one year;
e) where there is significant difference between the result of factory inspection and that of previous type inspection, and the factors causing the difference cannot be determined or their impact on product performance is unclear;
f) where type inspection is required by the national quality supervision organization;
g) where the user has specific requirements.
6.2 Batching
Under the condition that the raw materials and production process are not changed, the products of a tank or a kettle are considered as a batch.
6.3 Sampling
It shall be conducted in accordance with GB/T 4756. 4L samples shall be taken from each batch for inspection and reservation.
6.4 Judgment rules
The factory inspection and type inspection results shall be rounded off according to GB/T 8170, if the results conform to the technical requirements specified in Clause 5, the products shall be considered as acceptable.
6.5 Re-inspection rules
If any result of factory inspection or type inspection fails to meet the technical requirements of Clause 5, double amount of samples shall be taken and the unacceptable product shall be re-inspected according to the requirements of GB/T 4756. If any the re-inspection result still fails to meet the technical requirements, this batch of products shall be considered as unacceptable.
Contents of GB 12981-2025
Contents
Foreword Ⅲ
1 Scope
2 Normative references
3 Terms and definitions
4 Product variety and marking
5 Technical requirements and test methods
6 Inspection rules
7 Marking, packaging, transportation and storage
Annex A (Normative) Test method for evaporation performance of brake fluid
Annex B (Normative) Determination of pH value of brake fluid
Annex C (Normative) Test method for liquid stability of brake fluid
Annex D (Normative) Test method for corrosion of metal laminates by brake fluid
Annex E (Normative) Test method for low-temperature fluidity and appearance of brake fluid
Annex F (Normative) Test method for water insolubility and compatibility of brake fluid
Annex G (Normative) Test method for oxidation resistance of brake fluid
Annex H (Normative) Test method for rubber compatibility of brake fluid
