Vehicle maintenance is complicated and multifaceted, but it doesn’t have to be overwhelming. Your brakes are the first line of safety on the road, so it is important to keep them in good working order. Brake fluid is one of the best ways to do that.
Though there are other types of brake fluid on the market, DOT 3 fluids are reliable and trustworthy. For a formula with high temperature control, Peak Performance DOT 3 Brake Fluid is a top choice.
Vehicle brakes use a hydraulic system which needs fluid to generate pressure. Since water boils easily and creates rust, special fluids are designed for this purpose. Brake fluids combine a variety of solvents, lubricants, and corrosion inhibitors to make sure that the brake fluid doesn’t boil too quickly or freeze overnight.
DOT is short for Department of Transportation, which is the governing body that creates the standards by which brake fluids are judged. The numbering system started with DOT 1 and DOT 2, which are both obsolete now. Thus, DOT 3 is the baseline product, with DOT 4, DOT 5, and DOT 5.1 options available as well. The numerical system is primarily based on the boiling point of the brake fluid.
Boiling point has two aspects: dry and wet. The dry boiling point is when the brake fluid is new, and the wet boiling point is after the fluid has degraded over time. A brake fluid is considered ‘wet’ when it has absorbed 3.7% water, which usually takes around two years. The water absorption lowers the boiling point of the brake fluid, reducing its effectiveness.
For most vehicles, DOT 3 is a reliable and efficient brake fluid, but DOT 4 and 5 do have higher boiling points, which means they can take more of a beating. For some antilock braking systems, or ABS, DOT 4 may be recommended. Always check your manufacturer’s recommendations when selecting the proper brake fluid.
In addition to the DOT system, you will sometimes see brake fluids with an SAE rating—typically J1703—listed on the bottle. This means that the brake fluid meets or exceeds standards set by the International Society of Automotive Engineers. An SAE rating isn’t necessary to find a good brake fluid, but it is certainly helpful for peace of mind.
Most brake fluids have a service life of 2 years. There are brands that list a 3-year service life, which can certainly be a plus. Even if you change out your brake fluid in 2 years, using a brake fluid with a longer service life means it will be more resilient and not break down as easily as other options.
Don’t feel like you have to use the brake fluid produced by your car’s manufacturer. Many car companies offer brand-name brake fluids that cost a couple dollars more than the auto parts store brand. However, car company brand brake fluids are unlikely to be significantly better than STP or Lucas Oil and may actually be slightly worse. Opt for the brake fluid that is compatible with your car’s needs and don’t worry overly much about the name on the bottle.
The price range with brake fluids is really small—so much so that it’s almost irrelevant. Some brands will cost a couple dollars more than others, but the difference isn’t usually significant. On average, you can find a quart of good DOT 3 brake fluid for around $15-$20. If you spend less than $15, your brake fluid is likely to be cheaper and degrade faster. You may spend more than $20 on a quart from a premium brand, but the cost may be worth it as the quality improves proportionally.
A. The answer to this question varies widely from vehicle to vehicle. You might hear every 20,000 miles or every 40,000 miles, or you might hear every two to three years. Always refer to your owner’s manual to see what frequency of change is recommended for your vehicle. It’s also a good idea to change the brake fluid whenever you change your brake pads.
A. It’s hard to know for sure, but there are some things to look out for. If you look in the reservoir and your brake fluid is muddy or has debris in it, it’s time for a change. If your brakes aren’t functioning properly, you may be low on brake fluid or it may be time for a change.
A. Brake fluid is a fairly harmful chemical, so you need to be careful when disposing of it. The safest way is to check with your local waste authority for the best way to dispose of hazardous waste. You can also check with auto parts stores, as many will take old brake fluid in a closed container. If you absolutely must throw it away yourself, at least put it in a sealable, leakproof container first.
What you need to know: Reasonably priced and reliable, this heavy-duty formula provides effortless protection and lubrication.
What you’ll love: This formula resists corrosion and oxidation, has high temperature stability and maintains a high boiling point. This product easily lubricates rubber and metal parts and mixes well with other DOT 3 brake fluids.
What you should consider: This brand only offers one size container.
Where to buy: Sold by Amazon
What you need to know: Affordable and available in multiple sizes, this customer favorite delivers quality braking performance.
What you’ll love: This long-lasting formula shields brakes from wear and tear, protects metal from corrosion, and works well with disc, drum, and ABS brake systems.
What you should consider: Both the wet and dry boiling points exceed the minimum government standards.
Where to buy: Sold by Amazon
What you need to know: This inexpensive and resilient brake fluid can be mixed with other DOT 3 fluids.
What you’ll love: Made for disc, drum and ABS brake systems, this DOT 3 brake fluid has an extra-high boiling point and is resilient against high temperatures. It is available in 32-ounce and 1-gallon sizes.
What you should consider: Johnsen’s products are used by professional racing teams.
Where to buy: Sold by Amazon
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Collette Bliss writes for BestReviews. BestReviews has helped millions of consumers simplify their purchasing decisions, saving them time and money.