IT'S MORE THAN JUST OIL. IT'S LIQUID ENGINEERING.

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  5. 10W-40

SAE 10w-40 engine oil

If your car needs a SAE 10W-40 engine oil Castrol offers a range of options that flow like a 10 Weight oil when the engine is cold and a 40 Weight oil when up to normal operating temperature.

Image of a car's engine and oil next to text reading 10w40

What is 10w 40 oil used for?

CHOOSE THE BEST 10W-40 OIL FOR YOUR ENGINE

Castrol offers a broad range of 10W-40 engine oils, including  premium full synthetic, high mileage and conventional, meeting the needs of both drivers and vehicle manufacturers.


What is the advantage of 10W-40 oil? 

  • Castrol EDGE, an advanced full synthetic 10W-40 motor oil, is Castrol's strongest oil and a great option for those who want the very best for their car. 
  • Castrol GTX MAGNATEC is a premium full synthetic 10W-40 that offers superior wear protection. 
  • If your car has over 75,000 miles on the odometer, Castrol GTX High Mileage 10W-40 can help protect your emission system while helping to extend the life of your engine.
  • Castrol GTX 10W-40 Double-Action formula has been engineered to clean away old sludge while preventing new sludge formation.