DOT 5 silicone brake fluid is a very high specification fluid based on polydimethylsiloxanes (silicones) and offers many advantages over conventional glycol based fluids. Silicone fluid does not absorb water from the surrounding atmosphere while in service and therefore offers greatly extended service life whilst improving corrosion resistance of the main components of the braking system. Recommended for use in the hydraulic brake and clutch systems of all cars, commercial vehicles and motorcycles for which non-petroleum based fluid is specified. Particularly recommended for classic cars or vehicles that are garaged for much of their life but must be usable at short notice. This fluid must only ever be mixed with DOT 5 fluid which has the same silicone base. Never mix DOT 5 with regular glycol based fluids.
DOT 4 brake fluid is a high quality brake fluid recommended for use in the hydraulic brake and clutch systems of all cars, commercial vehicles and motorcycles for which a glycol based DOT 3 or DOT 4 fluid is specified. With a higher boiling point than DOT 3 fluid, this fluid is ideally suited for higher performance vehicles where the braking system routinely reaches moderate brake temperatures.
