Never Use Brake Fluid in Your Power Steering System: A Comprehensive Guide
Using the wrong fluid in your car can lead to costly repairs and even dangerous driving conditions. One common question that arises is whether brake fluid can be substituted for power steering fluid. The simple answer is a resounding no. Brake fluid and power steering fluid are fundamentally different, and mixing them will cause significant damage to your vehicle.
Understanding the Differences: Brake Fluid vs. Power Steering Fluid
Brake fluid and power steering fluid serve entirely different purposes and have vastly different chemical compositions. Let's break down the key distinctions:
Brake Fluid:
- Purpose: Brake fluid transmits hydraulic pressure from the master cylinder to the brake calipers or wheel cylinders, enabling you to stop your vehicle.
- Composition: Primarily composed of glycol ethers, a highly hygroscopic substance (meaning it absorbs moisture from the air). This moisture can corrode brake system components over time. Brake fluid has a very high boiling point, crucial for preventing vapor lock during heavy braking.
- Compatibility: Designed to work with specific brake system seals and components.
Power Steering Fluid:
- Purpose: Power steering fluid transmits hydraulic pressure from the power steering pump to the steering rack, making it easier to turn the steering wheel.
- Composition: Typically a petroleum-based fluid or a mixture of petroleum and synthetic fluids. It's formulated to lubricate the power steering pump and other components within the system. These fluids are not hygroscopic and generally don't absorb significant amounts of moisture.
- Compatibility: Designed to be compatible with the seals and components within the power steering system.
The Dangers of Using Brake Fluid in Your Power Steering System
Using brake fluid in your power steering system will have severe consequences:
- Corrosion: Brake fluid's hygroscopic nature will cause rapid corrosion of the power steering system's rubber seals and hoses. This leads to leaks, reduced steering assist, and ultimately, steering failure.
- Damage to Pump and Components: Brake fluid's chemical composition is incompatible with the materials used in the power steering pump and other system components. This incompatibility can lead to rapid wear and tear, requiring costly replacements.
- Steering Failure: As seals and components fail due to corrosion and damage, you will experience a significant loss of power steering assist. This can make steering difficult, especially at low speeds, potentially leading to accidents.
- Voiding Warranty: Using the wrong fluid will almost certainly void any applicable warranties on your vehicle's power steering system.
What to Do if You Accidentally Used Brake Fluid
If you mistakenly added brake fluid to your power steering system, immediate action is critical:
- Do not attempt to drive the vehicle.
- Flush the entire power steering system immediately. This requires professional assistance to ensure the system is thoroughly cleaned and refilled with the correct power steering fluid.
- Have a mechanic inspect for any damage. The corrosive nature of brake fluid may have already caused damage that requires repairs.
Conclusion:
Never attempt to substitute brake fluid for power steering fluid. The consequences can range from costly repairs to dangerous driving conditions. Always refer to your vehicle's owner's manual for the correct fluid specifications and consult a qualified mechanic if you are unsure. Using the proper fluids is essential for the safe and reliable operation of your vehicle.
