This specification describes the performance and part requirements for elastomeric seals used in highway vehicle disc brake calipers. Seals covered by this specification may be the solid section type (square, rectangular, O-ring, etc.) mounted stationary in the cylinder bore or on the movable piston. The specification contains the following major sections:

1

Resistance to Fluid at Elevated Temperature-Physical Stability (loose parts in 120 ±2°C (248 ±3.6°F) brake fluid for 70 h).

2

Resistance to Fluid at Elevated Temperature-Precipitation Characteristics (loose parts in 120 ±2°C (248 ±3.6°F) brake fluid for 70 h).

3

Resistance to Elevated Temperatures in Dry Air (loose parts in 175 ±2°C (347 ±3.6°F) air for 22 h).

4

Ambient Temperature Stroking Test (tested in brake assembly for 500,000 cycles to 7.0 ±0.3 MPa (1000 ±50 psi)).

5

High Temperature Stroking Test (tested in brake assembly for 70 h (70,000 strokes) at 120 ±2°C (248 ±3.6°F) to 7.0 ±0.3 MPa (1000 ±50 psi)).

6

Low Temperature Leakage Test (tested in brake assembly for 120 h at −40-42.8°C (−40-45°F)).

7

Cycling Humidity Storage Corrosion Test (tested in brake assembly for 14 days at 95% humidity cycling between 21-46°C (69.8-114.8°F)).