Choosing a seal material for Brake Fluid Dot3, Glycol Type
The table above rates every common O-ring elastomer for service in Brake Fluid Dot3, Glycol Type on an A–D scale. A is Excellent, B is Good, C is Fair (test before relying on it), and D is Not Recommended. An X indicates insufficient published data.
For Brake Fluid Dot3, Glycol Type, the strongest candidates are Ethylene Propylene, Silicone, Fluorosilicone, Neoprene (Chloroprene), Natural Rubber, Styrene Butadiene, Butyl, Aflas (TFE/P). These ratings are representative at ambient conditions (~20°C). Compatibility shifts with temperature, concentration, pressure and exposure time, so always validate the material against your real operating envelope before committing to a design.
