Rubber Dust Boots for the Hydraulic Disc Brake Piston
This SAE Standard covers molded rubber boots used on disc brake pistons to prevent the entrance of dirt and moisture which could cause corrosion and otherwise impair caliper operation.
The specification includes performance tests of brake piston boots of both plain and insert types under specified conditions and does not include requirements relating to chemical composition or physical properties of the rubber compound. Further, it does not cover the strength of the adhesion of rubber to the insert material where an insert is used.
The rubber material used in these boots is classified as suitable for operating in a temperature range of -40 to + 120 °C ± 2 °C (-40 to + 248 °F ± 3.6 °F).
Rationale: Sections 2.1.1 and 5.2 of this specification have been updated to create a reference to SAE J1703 and SAE J1704 where previous revisions listed the referee brake fluid formulation for DOT 3 fluid only. The industry is trending towards use of both DOT 3 and DOT 4 for global applications, and the formulation of the referee fluids is changing more rapidly. A direct reference to the brake fluid specifications will provide more accurate information as these referee brake fluid formulations change.