Purpose and Specifications

Castrol GTX 15W-40 is a premium mineral engine oil designed to protect gasoline and diesel engines from sludge buildup and wear. This 4-liter bottle delivers reliable protection for both modern and older vehicles, keeping your engine cleaner and extending its lifespan.

The 15W-40 viscosity rating means the oil flows easily in cold weather (winter starts at -15°C) while maintaining protective thickness at high engine temperatures (up to 100°C). This balance ensures your engine gets proper lubrication whether you're starting on a cold morning or driving in heavy traffic.

Key Performance Features:

• Removes existing engine sludge and prevents new buildup caused by heat, dirt, and short trips
• Keeps engines 35% cleaner than industry minimum standards
• Advanced anti-wear additives protect engine parts from friction and wear
• Protects against oil thickening and deposit buildup in critical engine components
• Better shear stability maintains consistent oil thickness throughout the oil change interval
• Suitable for turbochargers, multivalve systems, and catalytic converters

Meets Specifications: ACEA A3/B4, API SL/CF, VW 501.01, VW 505.00, MB 229.1, FIAT 9.55535-D2

When to Use and Replace

Use Castrol GTX 15W-40 in gasoline and diesel engines where your vehicle manufacturer recommends a 15W-40 oil meeting API SL or ACEA A3/B4 specifications. Check your owner's manual for the exact requirement.

Oil Change Intervals: Replace every 5,000 to 10,000 kilometers or 3 to 6 months, whichever comes first. Vehicles with frequent short trips, towing, or severe driving conditions may need more frequent changes (every 5,000 km). Modern engines with longer service intervals should follow the manufacturer's recommendation.

Operating Temperature Range: This oil performs reliably between -15°C (cold start) and 100°C (high-temperature protection), making it suitable for most climates.

Storage: Store in a cool, dry place. Shelf life is typically 3 to 5 years in unopened containers when stored properly away from direct sunlight.

Frequently Asked Questions

Q: Can I use Castrol GTX 15W-40 in both my gasoline car and diesel truck?
A: Yes. This oil is formulated for both gasoline and diesel engines. However, always verify your vehicle's owner manual first, as some engines require specific oil grades or specifications.

Q: What does the sludge protection actually do for my engine?
A: Sludge is a thick, tar-like substance that builds up inside your engine from heat and dirt. It clogs oil passages like cholesterol in arteries, reducing oil flow and causing wear. Castrol GTX's cleaning formula removes existing sludge and prevents new buildup, keeping oil flowing freely and protecting engine parts longer.

Q: Is this oil suitable for my older vehicle?
A: Castrol GTX 15W-40 is compatible with vehicles from 1995 onward with 4, 6, and 8-cylinder engines. If your vehicle is older or has specific requirements, check your owner's manual or consult a mechanic to confirm compatibility.