<Tr> <Td> DOT 5 </Td> <Td> 260 ° C (500 ° F) </Td> <Td> 180 ° C (356 ° F) </Td> <Td> 900 mm2 / s </Td> <Td> silicone </Td> </Tr> <Tr> <Td> DOT 5.1 </Td> <Td> 260 ° C (500 ° F) </Td> <Td> 180 ° C (356 ° F) </Td> <Td> 900 mm2 / s </Td> <Td> glycol ether / borate ester </Td> </Tr> <P> Wet boiling point defined as 3.7% water by volume . </P> <P> For reliable, consistent brake system operation, brake fluid must maintain a constant viscosity under a wide range of temperatures, including extreme cold . This is especially important in systems with an anti-lock braking system (ABS), traction control, and stability control (ESP), as these systems may use a valve with a time - based approach, rather than measuring pressure or volume to control the amount of fluid transferred . </P>

All of the following are properties of dot 3 and dot 4 brake fluid except