Because of the ingredients that make up brake fluid, the fluid attracts water, which could cause the fluid to boil during braking. This causes air bubbles in the braking system and reduces the braking effect drastically. Brake fluid has had a boiling point of approximately 230 degrees Celsius for many years. However, automotive manufacturers are increasingly switching to brake fluid with a safer boiling point of 260 degrees.
For instance, JLM DOT 4. A premium aftermarket brake and clutch fluid for the hydraulic brake systems and clutch systems of all passenger cars, vans and motorcycles, for which the manufacturer prescribes synthetic (non-petroleum based) fluids.*
JLM DOT 4 fluid exceeds the current international U.S. FMVSS No. 116 DOT 4 & DOT 3, SAE J1703 & 1704 and ISO (Classes 3 & 4) specifications. JLM DOT 4 brake fluid and clutch fluid is available in half litre packaging (J04840) and litre packaging (J04845). JLM DOT 4 can be mixed with other brake fluids that meet these specifications.