How to Recycle Brake Fluid
Hydraulic fluid used in brake and clutch systems, typically DOT 3, DOT 4, or DOT 5 formulations. Highly corrosive to paint and skin, toxic if ingested, and hygroscopic (absorbs moisture from air). Must be handled as hazardous waste due to glycol ethers and other toxic components.
- 1Ensure brake fluid is completely cool before handling
- 2Wear chemical-resistant gloves and safety glasses during handling
- 3Use brake fluid-specific bleeding equipment to avoid contamination
- 4Store only in original brake fluid container or clearly labeled hazardous waste container
- 5Keep container tightly sealed to prevent moisture absorption
- 6Never mix DOT 5 (silicone) with DOT 3/4 (glycol) fluids
- 7Clean up any spills immediately with water and dispose of cleanup materials with used fluid
- 8Keep away from painted surfaces - will damage automotive paint instantly
- Auto parts stores with hazardous waste programs
- Professional brake service shops and dealerships
- Municipal hazardous waste collection events
- Household hazardous waste permanent facilities
- Automotive quick-lube shops (some accept small quantities)
- Brake specialty shops and fleet maintenance facilities
HIGHLY CORROSIVE to paint, plastic, and rubber. Toxic if ingested. DOT 5 silicone fluid is NOT compatible with DOT 3/4 glycol fluids - mixing destroys brake system seals. Must be handled as hazardous waste in most jurisdictions. Never pour down drains or onto ground.
Contains toxic glycol ethers that persist in groundwater and are harmful to aquatic life. However, proper recycling through solvent recovery prevents environmental contamination. Brake fluid recycling recovers base solvents for reuse in industrial applications and new brake fluid formulations.
- Longer-life DOT 4 fluids reduce change frequency
- Professional brake services that guarantee proper fluid recycling
- Regular brake system testing to extend fluid life
- Closed brake bleeding systems to prevent fluid waste
Accepted
- DOT 3 brake fluid (most common, glycol-based)
- DOT 4 brake fluid (higher boiling point glycol)
- DOT 5.1 brake fluid (synthetic glycol, race applications)
- Clutch fluid (typically same as brake fluid)
- Power brake booster fluid
- Small quantities of contaminated brake fluid
Not Accepted
- DOT 5 silicone brake fluid (requires separate processing)
- Brake fluid heavily contaminated with oil or other fluids
- Brake fluid mixed with coolant or other automotive fluids
- Brake fluid in damaged or leaking containers
- Unknown fluid types that may not be brake fluid
Estimated value: $0 - typically costs $2-5 per quart for proper disposal as hazardous waste
- Glycol ethers (primary toxic component)
- Polyglycols and their derivatives
- Corrosion inhibitors and additives
- Antioxidants and preservatives
- Metal salts and pH stabilizers
What's the difference between DOT 3, DOT 4, and DOT 5 brake fluids?
DOT 3 and 4 are glycol-based with different boiling points (DOT 4 is higher). DOT 5 is silicone-based and NOT compatible with DOT 3/4. DOT 5.1 is synthetic glycol with very high boiling point. Never mix different types.
Can I mix different DOT ratings for disposal?
You can mix DOT 3, DOT 4, and DOT 5.1 (all glycol-based) for disposal. NEVER mix DOT 5 silicone fluid with glycol fluids - it requires separate handling and can damage brake systems if mixed.
Why is brake fluid so corrosive to paint?
Brake fluid contains strong solvents that dissolve paint binders instantly. Even small drops will create permanent paint damage within minutes. Always use drop cloths and clean spills immediately with water.
How often should brake fluid be changed?
Every 2-3 years for most vehicles, or when moisture content exceeds 3-4%. Brake fluid is hygroscopic and absorbs moisture, which reduces boiling point and causes internal corrosion.
Can I pour brake fluid down the drain if I dilute it?
NO. Brake fluid is classified as hazardous waste and is illegal to dispose of in drains or regular trash. Even diluted brake fluid contains toxic glycol ethers that harm water treatment systems.
What should I do if brake fluid gets on my skin?
Wash immediately with soap and water. Brake fluid can cause skin irritation and is toxic if absorbed. If it gets in eyes, flush with water for 15 minutes and seek medical attention.
Can I test brake fluid to see if it needs changing?
Yes! Use brake fluid test strips to check moisture content and copper levels (indicates internal corrosion). Testing can help determine actual replacement needs versus following rigid schedules.
Is it safe to store brake fluid long-term?
Store in original sealed containers in cool, dry places. Brake fluid absorbs moisture from air, so opened containers deteriorate quickly. Use within 1-2 years of opening.
What happens to recycled brake fluid?
It goes through solvent recovery to separate base chemicals from contaminants. The recovered solvents are reused in new brake fluid production or industrial applications, preventing environmental contamination.
Can I use old brake fluid for anything else?
No - brake fluid degrades over time and contaminated fluid should never be reused. Its corrosive properties make it unsuitable for any DIY applications. Always dispose of properly.