The reason for brake fluid maintenance in the absence of any mechanical failure is because brake fluid is hydrophilic, meaning it absorbs 3% of its weight in water every year. Under normal conditions 5-10% of the fluid could become water in just a few years. Makes sense if you understand how the brake system works and that its job is to stop the vehicle by delivering pressure from one mechanical component to another. High pressure in the brake system leads to high temperatures that overheat the fluid and result in brake fade. While a reduction in braking performance isn’t welcome, it isn’t the only concern as brake fluid is converted to water. 

Many components of the braking system are manufactured with steel, such as the brake lines, and with an elementary understanding of chemistry, it’s not difficult to see why excess water in the system is a bad thing. When we mix water and steel, we get corrosion and pitting which wears seals when rubbed against corroded surfaces. But wait, there’s more… 

Small particles of dirt can contaminate the fluid over time, affecting antilock braking systems (ABS) and traction control systems which are sensitive to moisture and foreign particles– If brake fluid is not pure and clean, these systems will be affected and lead to more expensive repairs. Brake fluid should be changed every 2-4 years and not necessarily based on miles driven because unlike other fluids used in a vehicle, the amount of time between changes is the dominating factor. 

The best way to maximize this service opportunity is to talk to your customers. Find out when their last brake fluid service was and educate them on the importance of this routine maintenance.