WHY CHANGING BRAKE FLUID IS SO IMPORTANT
ZF Aftermarket experts recommend regular inspections and a yearly fluid change
High-quality brake fluid is crucial in ensuring continued stopping power, with ZF Services Australia recommending workshops regularly remind customers to have their brake fluid checked, with yearly changes advised.
Brake fluid plays a vital role in ensuring the smooth operation of the braking system, and like all lubricants, the oil degrades over time, regardless of mileage.
Deteriorated brake fluid can impact on the operation of the various components in the braking system, which in a worst case scenario could lead to brake failure.
ZF Aftermarket experts have produced the below helpful tips on how to check the condition of brake fluid, quickly and reliably. Armed with this knowledge, ZF says workshops can offer customers a wider range of services, and improve the safety of their cars.
Severe overheating can lead to total failure
Hydraulic fluid resides in the lines, tubes and reservoirs of the brake system in various configurations of disc and drum brakes, transmitting pressure whenever the brake pedal is engaged, with additional power provided by brake boosters.
There are various influences that can greatly affect the liquid over time, including severe overheating, which can occur with prolonged engagement over extended gradients, in turn causing the fluid to boil. This can then lead to an evaporative reaction, and the formation of air bubbles.
When the brake pedal is pressed again, the bubbles are compressed, but the braking force may be lessened or not transmitted at all, ultimately leading to brake failure.
Another common fault found in braking systems is the ingress of water, with the entry point often being the breather hole in the cover of the tank, which is designed to provide ventilation in the event of fluctuating brake fluid levels.
However, atmospheric humidity can also enter the system via this ventilation hole. Additionally, water can make its way into the overrun tank through the ventilation hole when the engine bay or vehicle is cleaned.
Brake hoses and sealing elements can also be responsible for increased water levels in the brake fluid, as water can diffuse through these parts, especially when they age.
Venting device for reliable repair results
On average, brake fluids have a water content level of around 0.05 percent, with the value typically trending upwards over time.
If the water content level exceeds 3.5 percent, it is strongly recommended that the fluid be changed, as the wet boiling point has been reached. When the three percent mark is exceeded, the boiling point of the fluid drops to between 140 and 180°C.
ZF says it offers a range of specialist tools for brake fluid changes, as well as the broad portfolio of TRW brake fluids, which are suitable for most vehicle types.
TRW brake fluids reportedly ensure optimal braking behaviour from -50°C to +50°C, with enhanced protection against corrosion, and compatibility with the sensor systems installed in late model cars, such as ESP.
For more information, visit www.trwaftermarket.com or contact ZF Aftermarket via 02 9679 5555.