PSA B71 6000 Material Compatibility Tests - Reference Fluids for Material Compatibility Tests

The “PSA B71 6000 Material compatibility tests – Reference fluids for material compatibility tests” standard, developed by the French automotive manufacturer PSA Group (now part of Stellantis), defines the fluid to be used when a material or part is required for material compatibility testing. For continuous contact, if a specific fluid is not specified in the functional drawing or technical specification, material compatibility tests are performed with the reference fluid specified here.

Fluids for testing under the PSA B71 6000 standard are listed as follows:

• Lubricants
• Engine oil
• Manual transmission and gearbox gear oil
• Automatic transmission oil
• air conditioner compressor oil
• Power steering fluid and suspension fluid
• Engine oil for special tests.
• fuels
• Diesel fuel
• Petrol
• Automotive fluids
• Synthetic hydraulic fluid (brake fluid)
• coolant
• Window cleaning fluid
• Selective catalytic reduction (SCR) liquid
• Diesel particulate filter (DPF) fluid
• Other liquids
• Assembly aids
• 12V liquid battery
• Road salt solution
• Acidic and basic solvents
• Car interior cleaning products
• Exterior car wash products
• Wheel cleaning product

The PSA B71 6000 standard defines reference fluids used in standardized test procedures to assess the compatibility of various automotive fluids with materials, particularly plastics, rubbers, elastomers, and coatings.

In vehicle design and manufacturing, components such as gaskets, hoses, seals, fuel lines, and internal parts come into contact with fluids such as fuel, engine oil, coolant, brake fluid, transmission fluid, windshield washer fluid, and battery acid. Incompatibility can lead to:

• Swelling, cracking, or softening of materials
• Leakage or malfunction in components
• Decreased vehicle durability and safety.

To ensure reliability, automakers like PSA specify standardized reference fluids—synthetic or formulated blends that simulate real-world automotive fluids under extreme conditions. These allow for consistent and repeatable testing between suppliers and laboratories, rather than using variable commercial fluids.

The PSA B71 6000 standard defines the composition, properties, and sources of these reference fluids used in other PSA testing methods (e.g., immersion tests, aging cycles, or exposure simulations).

PSA has several interconnected standards for fluid-material interactions:

• The standard “PSA D47 1924 Plastics and rubbers – Occasional contact with vehicle fluids” includes a test method for the effects of vehicle fluids on plastics and rubbers (occasional or prolonged contact). This standard explicitly refers to specific fluids and procedures.
• The standard “PSA D47 1309 Aging of automotive equipment materials and parts according to a specific climate cycle” defines the aging climate cycles to be applied to automotive equipment materials or parts.

These standards are specific to PSA/Stalantis and, being exclusive to suppliers and testing partners, are generally not publicly available in all their details.

In general, typical reference fluids in these standards include the following:

• Reference fuels (e.g., gasoline or diesel blends containing additives for aggressiveness)
• Reference engine oils
• Coolant mixtures
• Brake fluids (DOT type simulations)
• Aggressive cleaners or acids

The tests involve immersing samples in these liquids at high temperatures and then measuring changes in volume, weight, tensile strength, or appearance.

From a supplier's perspective, materials approved according to PSA norms must pass compatibility tests using PSA B71 6000 fluids before they can be used in vehicles. This standard ensures the long-term reliability of fluid-exposed parts for vehicle owners and mechanics, reducing problems such as hose degradation or gasket failures. This standard highlights rigorous background testing that contributes to vehicle safety and longevity in modern automobiles.

In short, the PSA B71 6000 standard plays a critical role in automotive engineering by defining standardized reference fluids used to test the compatibility of materials with vehicle fluids. Its importance stems from ensuring consistency, reliability, safety, and quality throughout the supply chain and in the final vehicles. This standard is considered important for the following reasons:

• It provides repeatable and comparable test results: Real-world automotive fluids (e.g., fuels, oils, coolants) vary in composition due to brand, additives, regional formulations, or degradation over time. Reference fluids are precisely formulated blends that simulate the most aggressive or worst-case characteristics of these fluids.

This standardization enables laboratories and suppliers worldwide to perform the same tests, ensuring consistent results that can be directly compared. This is crucial for material approval in Stellantis instruments.

• It prevents material failures and increases vehicle durability: Incompatible materials can swell, crack, soften, harden, or release chemicals when exposed to liquids. This can lead to:
• Leaks in fuel systems, hoses, or seals.
• Brake or transmission failures.
• Decreased performance of seals, O-rings, or plastic components.

This standard mandates testing with defined reference fluids, helping to identify risks early, prevent costly field failures, and extend component life.

• Supports safety and regulatory compliance: Automotive parts must withstand harsh conditions without compromising safety. Standardized testing aligns with broader industry needs for reliability under extreme temperatures, oxidation, or chemical exposure. By preventing premature material degradation, it contributes to meeting global regulations related to emissions, fuel efficiency, and vehicle safety.

For many years, our organization, with its competent and experienced staff, has been understanding the needs of its clients, providing the advanced testing services they require, and assisting in the establishment, implementation, and improvement of management systems. Within this framework, we also provide testing services in accordance with the "PSA B71 6000 Material compatibility testing - Reference fluids for material compatibility testing" standard.