Description / Abstract:
This SAE Recommended Practice was prepared by the Motor Vehicle
Brake Fluids Subcommittee of the SAE Hydraulic Brake Actuating
Systems Committee to provide engineers, designers, and
manufacturers of motor vehicles with a set of minimum performance
standards in order to assess the suitability of silicone and other
low water tolerant type brake fluids (LWTF) for use in motor
vehicle brake systems. These fluids are designed for use in braking
systems fitted with rubber cups and seals made from natural rubber
(NR), styrene-butadiene rubber (SBR), or a terpolymer of ethylene,
propylene, and a diene (EPDM).
In the development of the recommended requirements and test
procedures contained herein, it is concluded that the LWTFs must be
functionally compatible with existing motor vehicle brake fluids
conforming to SAE J1703 and with braking systems designed for such
fluids. To utilize LWTFs to the fullest advantage, they should not
be mixed with other brake fluids. Inadvertent mixtures of LWTFs
with fluids meeting SAE J1703 are not known to have any adverse
effects on performance, but all combinations have not been tested.
Vehicle manufacturer's recommendations should be followed where
indicated. These fluids are not necessarily suitable for use in
central hydraulic or pumped systems and are not intended for use
below temperatures of -50 °C (-58 °F). Brake fluids covered under
this document are not required to tolerate water and extreme
caution should be exercised to prevent accidental entry of water
which might lead to brake failure. Other performance
characteristics of these LWTFs not covered in this document are
discussed in Appendix A.
Rationale—
This document has been found to be Noncurrent, therefore, it may
be in use by some areas of industry but is not the most up-to-date
technical information.