J & M Auto Parts: Brake Fluid

Brake fluid is hot! It reaches its boiling point when it is pushed, under pressure through your brake lines to the brake caliper every time you step on the brake pedal. At J & M Auto Parts we know you have everything riding on your brakes. Come by J & M Auto Parts at 301 Quincy Ave or call 540-652-4415 and discuss which brake fluid is right for your truck or car.

Brake fluid is designed to withstand intense heat by having a boiling point higher than water. The DOT number printed on the container tells drivers about the use and boiling point of the brake fluid. Look for the letters DOT (Department of Transportation) followed by the number 3,4,5.1 or 5.

DOT 3 and 4 Brake Fluid

DOT 3 and DOT 4 are the most common types of brake fluid in cars in Shenandoah. Your owner's manual will explain which one you need for your car. DOT 3 and DOT 4 brake fluids are both hygroscopic, golden-colored glycol-based fluids that absorb moisture out of the air. Water has a boiling point of 212 degrees but DOT 3 brake fluid has a boiling point of 401 degrees. This is why your brake fluid can handle the extreme heat and pressure created by the braking system.

The boiling point of DOT 4 brake fluid starts at 486 degrees and it is quickly becoming the standard in new cars. DOT 4 is used in both foreign and domestic vehicles. The additives in DOT 4 make it ideal for high-performance vehicles and racing. Mixing DOT 3 and DOT 4 brake fluid is not recommended. DOT 3 and 4 brake fluids are ideal for driving in normal stop-and-go traffic in Shenandoah. Give us a call at 540-652-4415 or stop by at 301 Quincy Ave to discuss which DOT is right for your car.

DOT 5.1 Brake Fluid For Racing

DOT 5.1 is a glycol-based brake fluid like DOT 3 and DOT 4. It has a 516 degrees boiling point appropriate for applications similar to DOT 4 racing brake fluids. DOT 5.1 is preferred by driving enthusiasts in Shenandoah. DOT 5.1 is a higher price than DOT 3 but well worth the extra cost for racing applications. DOT 5.1 Brake fluid should not be mixed with other types of brake fluid.

Brake Fluid Break Down

Over time DOT 3, 4, and 5.1 brake fluids will become dirty and acidic, clogging valves and corroding the braking system of drivers in Shenandoah. The efficiency of degraded brake fluid drops to 284 degrees boiling point and becomes ineffective during heavy braking. Make sure to change your brake fluid and service your brakes regularly.

DOT 5 Silicone Brake Fluid

DOT 5 brake fluid is silicone-based, with a very high boiling point of 500 degrees. It is preferred for heavy-duty and military vehicle applications because it does not corrode the system over time. The price of DOT 5 brake fluid is slightly more than the cost of DOT 3 brake fluid. Cars and trucks made with anti-lock (ABS) braking systems should not use DOT 5 brake fluid. If a small amount of water vapor is introduced into the brake line DOT 5 brake fluid will become foamy in an ABS system causing the brakes to fail. DOT 5 does not absorb water, therefore, water may accumulate on the calipers and convert to steam causing immediate brake failure.