I have a 2003 Ford Crown Victoria with about 75,000 miles. I have recently done a brake fluid change. From the look of the old fluid, it looks like the brake fluid had never been changed. It had a blue-green tinge to it, which suggests there is oxidized copper in it. In my other cars, When I lived in L.A., where it is extremely dry, I usually had brake fluid changed every 2-3 years. I have never seen blue-green tinge to the old brake fluid, and the brake pedal feel had never changed due to the fluid change. When I bled the brake on the Crown Victoria, there was not air coming out, so the spongy feel before the fluid change was not due to air in the system.
Anyway, after the brake fluid change, the brake feels much less spongy and certain. When I was test driving the Crown Victoria, I thought the spongy feeling in the brake was normal, since it is designed for people who learned to drive before the 1970s. Now, the brake feels closer to how Honda Accord and Nissan Maxima felt.
Question:
Is it normal for the brake to feel more solid and certain after a fluid change?
The bleeding process changed the “feel”, not the fluid itself…Does your car have ABS brakes? Bleeding an ABS system can change its feel…
" I thought the spongy feeling in the brake was normal, since it is designed for people who learned to drive before the 1970s." And you base this observation on what?
I guess that @Roger124; must think us old foggies don’t know what a good brake pedal feels like.
I’m heading out right now to test drive an Accord and a Maxima so I can learn what new fangled things they’ve done with cars since I bought my old Model T.
Fluid does make a difference in pedal feel. Here’s what a brake manufacturer has to say about it.
Once brake fluid soaks up moisture it thickens and will not be able to withstand the heat create under the pressure of heavy braking. What happens next is a significant drop in the fluids boiling temperature (wet boiling point). When the fluid boils it turns into vapor and forms air bubbles, and this can result in more pedal travel to properly apply the brakes (soft pedal).
I can understand how new brake fluid will change the feel after repeated heavy braking and the brake fluid is hot, but how does it change the feel otherwise?
Old, nasty, contaminated brake fluid will be more compressive that fresh brake fluid.Brake fluid is hydrophilic, meaning that it will absorb moisture from the air. That moisture changes the boiling point of the brake fluid. Simply bleeding the brakes also removes some of the trapped air within the brake circuits. No system is perfect, and very small amounts of air get into the brake system through normal use. Changing the brake fluid also bleeds the system, removing all of this bad stuff and restoring the brakes to proper function. Every time I’ve done a brake fluid change, the difference in the brake pedal is noticeable. If it is really old and nasty, the change is dramatic.
Hmmm, I gotta tell ya, that 64 Ford I had for drivers training had pretty sticky brakes. More than once the instructor paniced and squeeled the tires. Of course the manual brakes in the 61 Chevy is what I really remember.
I gotta go and work on the sign now that says “stay off my grass”. Danged kids now will walk anywhere. Good thing for them though they’ll inherit all our money.
A few months ago, the driver of a 10 year old Econoline van was complaining about a mushy brake pedal. He was worried that the vehicle might need expensive repairs
I determined that the van was still on the original brake fluid
After a thorough brake fluid flush, the pedal was again normal, and the driver was happy that his vehicle was repaired quickly . . . and cheaply
I wonder if gas (air) accumulates as a by product of corrosion. It is not unusual to see a few bubbles escape when bleeding a ten year old brake system.
The majority of internal corrosion comes from moisture absorbed by the brake fluid, I believe. If I remember my chemistry right, moisture breaks down metals by attaching the oxygen molecule to metal, freeing the hydrogen. So, yeah, corrosion seems to create gas accumulation.
All new brake fluid is clear, but I wouldn’t worry, if it is yellow or tan. But if it’s brown, it’s definitely time to change. So, your brake fluid should look clear to yellow.
@Juanita - if you don’t know when the brake fluid was last changed, it’s time. Brake fluid can look good even if it has absorbed water. Replacing the fluid in the reservoir, followed by bleeding the brakes (making sure the reservoir doesn’t get too low) would be the thing to do.
Not to out do @Roger124; but not all brake fluid is clear when it’s new.
I worked on a BMW that takes a silicone based Brake fluid that is blue…out of the bottle.
I just would not want someone with a new car that takes this fluid to think there’s something wrong with the fluid.