From the experts at Bendix

Bendix says that according to research, many motorists do not understand the critical role that brake fluid plays in braking, nor do they know or understand why this should be tested and changed regularly.
In this important area the mechanic plays a vital role in explaining why testing and changing brake fluid during a vehicle service is important to vehicle and passenger safety.
Leading Brake manufacturer Bendix provides some helpful tips to pass on to your customers plus information on the correct procedures to test and change this important fluid.
A special video can be watched at to assist in this process.
When changing brake fluid, the experts at Bendix recommend using the hard-working formulas of Bendix High Performance DOT 3 or DOT 4 brake fluids as these are a high performance Polyglycol type fluid designed for the optimum performance of hydraulic and conventional brake systems.
Brake fluid is designed with a high boiling point to withstand the extreme temperatures generated during braking and needs to be checked to ensure it meets the exact temperature requirements.
Both DOT 3 and DOT 4 are hydroscopic fluids which absorb moisture when exposed to air. This can occur in instances where the reservoir cap is opened or through brake lines where the moisture level can build up over time through microscopic pores in the line.
This is a normal process of the brake fluid’s life cycle and moisture absorption prevents pooling and corrosion on metal components in the system.
Elevated moisture levels over time reduce the boiling point of the fluid, resulting in a reduction of effectiveness of the brake fluid.
In hot weather conditions or under heavy vehicle braking, moisture can vaporise, causing the system to lock leading to a soft brake pedal or complete brake failure.
Two common tools are used to test brake fluid, being a Conductivity Tester or a Boiling Point Tester. Conductivity Testers estimate the moisture content by converting the conductivity into an estimated boiling point.
Since brake fluids vary in formula, Bendix says such a test will not provide a result unless the tester is calibrated to the manufacturer’s product when new.
The tester recommended by Bendix is one that heats the brake fluid to determine the correct boiling point.
Such a test takes less than a minute to accurately measure the boiling point and confirm if the brake fluid has absorbed too much moisture to be safe.
“In just twelve months brake fluid will have absorbed approximately two percent water reducing its boiling point by 75 degrees,” Bendix Marketing Services Manager, Ian Bott, said.
“Once the brake fluid has been changed it is important to bleed the system to remove any air bubbles trapped in the line which may cause a spongy brake pedal and in extreme cases, brake failure.
Go to the special video at for further assistance.”
Bendix DOT 3 High Performance Brake Fluid is suitable for use in ABS/non-ABS disc and drum brakes and hydraulic clutch systems in cars, trucks, buses and motorcycles where FMVSS DOT 3 fluids are specified. This fluid is straw in colour for ease of identification.
Bendix DOT 4 High Performance / Heavy Duty Brake Fluid is suitable for use in ABS/non-ABS disc and drum brakes and hydraulic clutch systems in cars, trucks, buses and motorcycles. DOT 4 fluid is dyed blue in colour for easy identification.
Bendix DOT 3 and DOT 4 brake fluids are available in 500ml and 4 litre bottles plus 20 litre drums and instructional Bendix videos can be viewed at

For further information free call the Bendix Brake advice Centre on 1800 819 666 or +61 3 5327 0211 from overseas – 8am-5pm Monday to Friday EST, email or visit