Brake fluid and the importance of changing it regularly

The recommended intervals for changing your car’s brake fluid varies slightly, but it is usually every 2 years (this information applies only for normal city/street driving, high-performance and racing use has totally different requirement than what we discuss below) .

Why is it important to replace the brake fluid?

The brake fluid that is used in the majority of late model Audi, Porsche, Bentley and VW is “hygroscopic”, which means that it naturally absorbs moisture from the air. According to engineers, that absorption rate is approximately 1.5 to 3% a year in areas of normal atmospheric pressures. In humid climates, that rate can climb even higher.  As brake fluid absorbs more and more water, it will begin to boil at lower and lower temperatures, so stopping ability can diminish in hard stops as heat in the system increases. If your brake fluid has become dirty or contaminated, it can change how your brake system operates — brake pedal feel can be affected. In addition, over time the moisture can cause internal corrosion in the ABS/ESC pump, brake lines, calipers, master cylinder, and other brake system components.

Flushing and replacing the brake fluid might cost less than replacing ruined ABS/ESC pumps, rusted brake lines, brake calipers and other brake parts which can run several hundred to thousands of dollars. Clearly, there’s value in keeping up with maintenance. A great practice is to follow strictly your scheduled maintenance for your car to replace your brake fluid regularly. Drivers living in areas that get winter weather or in places with high humidity should also inspect their brake system frequently.

Sometimes, you might be able to tell it’s time for a change by looking at brake fluid color in the brake fluid reservoir (especially if you do not know when it was last replaced), usually sitting on top of the master cylinder under the hood of your vehicle. Brake fluid is often light brown in color (sometimes it may be blue), and in some vehicles it’s clear (at least when new) but will darken with age (after 4-5 years), becoming murky from water contamination. The best way is to test it’s water % using a brake fluid test tool or just take it in to a professional shop to get tested/replaced.

How often we should change the brake fluid?

Every car manufacturer has a different interval for brake fluid flush/change. If your car is using genuine brake fluid, then for mot Audi, Porsche, Bentley, and Volkswagen (VW) models, brake fluid should be changed usually every 2 years, regardless of mileage (in some cases the first change should be 3 years after purchasing a new vehicle and then every 2 years afterwards.

If you ever notice your car has decreased stopping power, have it inspected by a certified mechanic. Bestiale can certainly help with this or if you want to schedule your appointment for a brake fluid replacement/flush.

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