Purpose and Specifications

Castrol 15CD1B is a premium DOT 4 brake fluid in a 5-liter bottle, nitrite-free and synthetic for reliable braking in disc, drum, or ABS systems, plus hydraulic clutches. It delivers a high boiling point over 250°C dry and 165°C wet, preventing vapor lock during hard stops so brakes stay firm up to extreme temps.

Key practical perks: Superior corrosion protection from moisture cuts maintenance costs; stable at high heat for safety margin; controls rubber swell for smooth component action; mixes with other DOT 3/4 fluids.

When to Use / Replace?

Perfect for daily drivers, city stop-go, hills, or heavier loads. Use in cars from 1959-2025 like VW Golf, BMW 3 Series. Replace every 2 years or per manufacturer schedule, or after 50,000 km in tough conditions, as it absorbs water over time. Shelf life is 5 years unopened.

• High heat resistance: Safe braking above 200°C.
• Operating range: -40°C to over 250°C.
• 5L fills most systems fully.

FAQ

Is Castrol 15CD1B safe for ABS brakes? Yes, fully compatible with ABS, disc, drum, and clutch systems for crisp response.

How often change brake fluid? Every 2 years or 50,000 km; check if brakes feel spongy.

Can I mix with other DOT 4? Yes, but for top performance, flush and refill with pure Castrol.