View Single Post
  #34 (permalink)  
Old 09-01-2020, 08:29 PM
CSXBill CSXBill is offline
CC Member
Visit my Photo Gallery

 
Join Date: May 2020
Cobra Make, Engine: Shelby CSX6000, Superformance MKIII, Factory Five 289 FIA custom
Posts: 23
Not Ranked     
Default

Quote:
Originally Posted by Dwight View Post
What Is Brake Fluid Made Of?
If you look at the chemistry behind most brake fluid, it comes from the combination of various types of glycols, which are basically a mixture of non-petroleum and other alcohol-based fluids. After a mixing process, the chemical name gets shortened to “polyglycol”. In addition, there are also high-grade silicone-based fluids, which cannot be mixed with any other type of fluid. So whether it's used in the brake or clutch system, it's important to understand the differences between these common types of brake fluid.

The brake fluid must maintain specific properties. Our brakes can get hot, sometimes up to 1200 degrees, so the fluid needs a high boiling point. Also, because our vehicles experience seasons just as we do, it’s important to have low freezing point as well. On top of maintaining both extremes, it's designed not to damage any rubber components in the brake system.

brake fluid properties
As a result, the chemical properties found in most brake fluids can permanently dull or damage paint. So be sure to handle with care and be quick to clean any accidental overspills. Brake fluid is hydroscopic, meaning it has a natural tendency to absorb moisture. And over enough time the added moisture can result in corrosion build up or a decreased boiling point. It’s never a bad idea to change your brake fluid every couple of years and try not to leave your reservoir cap off any longer than needed.

DOT 3 vs DOT 4
DOT 3

DOT 3 is the most common type of brake fluid used in domestic cars and trucks. According to the Society of Automotive Engineers (SAE), DOT 3 can absorb 2 percent of its volume in water every year. Over enough time excessive moisture will cause corrosion in the brake system which can lead to issues like vapor-lock or a spongy pedal.

DOT 4

DOT 4 is formulated for use by all vehicles, it has a higher boiling point than DOT 3 and it does not absorb moisture as fast. DOT 4 and DOT 3 are interchangeable, however it's best to avoid adding DOT 3 fluid to a system that already uses DOT 4. It's the preferred type of fluid used for street and high performance applications. Almost all of the brake fluids Speedway offers from Afco, Wilwood, and Ultra Lite will meet or exceed DOT 4 requirements.


I added the bold print so it would be easier for the speed readers
Dwight
Great info!
Reply With Quote