What Causes Brake Noise After Changing Brake Fluid?
3 Answers
After changing the brake fluid, the reasons for brake noise include rust on the brake discs, noise from the suspension system, or failure of the brake caliper, as detailed below: Rust on Brake Discs: Brake noise can occur due to rust or hard spots on the brake discs, typically noticeable when the vehicle first starts moving. Suspension System Noise: Noise from the suspension system or pressure bearings may occur because cold weather hardens rubber components, leading to noise when braking. This usually improves after the vehicle warms up. Brake Caliper Failure: Check if the brake caliper is malfunctioning, which could cause noise. It is recommended to have it inspected at a 4S shop.
I've encountered a similar situation before. After changing the brake fluid, the brakes made a squeaking noise when pressed. At first, I thought it was a minor issue, but upon inspection, it turned out that air had entered the brake system. If air isn't completely purged during the fluid change, bubbles can form, affecting hydraulic transmission and causing brake noise, often accompanied by a spongy feel. Additionally, the brake pads and rotors might become mismatched due to improper handling during replacement, such as insufficient lubrication from the new fluid or accidental scraping that leaves debris on the surface. Another possibility is inadequate lubrication of the caliper guide pins or slight deformation of the brake pads themselves. If this happens, don't delay—return to the repair shop immediately for a thorough recheck to purge air and adjust components. That's how I resolved my issue, and I also had the entire brake system inspected to prevent potential hazards. Remember, don't attempt DIY fixes; leave professional tasks to professionals. Driving safety comes first.
Last time I helped my friend replace the brake fluid, he complained about a constant clunking sound when braking after just two days of driving, which was quite alarming. Upon inquiry, I learned that the common causes include incomplete air bleeding during the fluid replacement, leading to air bubbles mixed in the brake fluid, which affects pressure transmission and causes noise. Sometimes, it's also due to a reaction between the new and old fluids, creating impurities that clog the lines. Or, the brake pads might have been installed incorrectly, with misaligned friction surfaces shifting during operation and triggering noise. I advised him to gently pump the brakes a few times to release any trapped air first. If the noise persists, he should return to have a mechanic use professional tools to bleed the system and inspect it. Such minor issues in daily driving should never be overlooked; addressing them early ensures peace of mind. Otherwise, braking performance could be compromised, especially on mountain roads or during rainy conditions, which is particularly dangerous.