Understanding Brake Fluid Colors for Maintaning Your Car
Brake Fluid Colors: Your Infiniti G37’s braking system is a sophisticated assembly of components fine-tuned to deliver the stopping power needed for safe driving. While brake fluid is only part of that system, it’s an important contributing factor to its performance and reliability. Keep reading to learn about brake fluid color, temperature and testing methods, plus what you should know when buying new fluid.
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Brake Fluid Colors
Glycol ether fluids can exhibit a variety of shades, but only silicone-based DOT 5 is purple. You should never put DOT 5 in a vehicle that takes DOT 3, 4 or 5.1, and vice versa. When the two types mix, they form a thick gel that can render your brakes inoperable. You’ll know glycol ether brake fluids by their unique colors and tints:
- DOT 3: Light yellow, blue, red or green
- DOT 4: Colorless, yellow or deep red
- DOT 5.1: Yellow, blue or crystal
Regardless of its specific shade, brand-new fluid out of the bottle is typically clear or translucent. Gritty or cloudy fluid indicates contamination and possible excess moisture. Dark honey, brown or black fluid should also be changed immediately.
Testing Your Brake Fluid
Brake fluid is referred to as either “dry” or “wet.” Dry fluid is fresh and in its original unopened container. Wet fluid has absorbed at least 3.7% moisture: It typically reaches this state after about two years of regular driving. Fortunately, you don’t have to wait for your fluid to turn colors or collect debris to know its condition. You can discover this information through one simple tool: a brake fluid tester.
Brake fluid is hygroscopic, which means it naturally absorbs moisture. Even when your brake lines are properly installed, they still have very tiny pores and seams through which moisture invades. With a brake fluid tester, you can regularly check your fluid’s moisture content.
Individual driving habits determine the proper frequency of brake fluid changes. Use your brake fluid tester to check moisture levels whenever you change your oil, which is recommended every 5,000 to 8,000 miles. Most testers are designed to check glycol ether fluids, so read each one’s specs carefully before you buy.
Needs for Your Specific Make & Model
The DOT develops regulations for brake fluid composition and heat tolerances to ensure dependable performance. Friction and heat go hand in hand: Hence, each fluid grade has boiling points to ensure that it can handle the high temperatures generated when the calipers and pads clamp onto the rotors. Note each grade’s dry and wet boiling points respectively:
- DOT 3: 401°/284° F
- DOT 4: 446°/311 °F
- DOT 5.1: 518°/374°F
Every vehicle has unique needs when it comes to brake fluid. Vehicle specs and driving conditions usually dictate those needs. Before buying brake fluid for the first time, check your owner’s manual for specific recommendations.
Buying Your Brake Fluid
Like many vehicles, your Infiniti G37 can use either DOT 3 or DOT 4 brake fluid. Once you’ve first purchased a specific grade of Infiniti G37 brake fluid, you should continue to use the same type. Your preferred auto parts and accessories retailer carried a large selection of fluids to help meet your auto maintenance needs.