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20W-50

A 20W-50 motor oil is typically used in older vehicles or in particularly warm climates. Castrol GTX 20W-50 has been specially formulated to help extend the life of your engine by keeping it free from sludge, even when operating in extremely high temperatures.

Getting the best 20W-50 oil for your vehicle

Whether you choose high mileage 20W-50 or conventional  20W-50 motor oil, they will both flow like a 20 Weight oil in cold weather, then with the viscosity of a 50 Weight oil once the engine is up to full temperature. Choose Castrol® GTX® 20W-50 to protect against sludge and Castrol® GTX® High Mileage for older vehicles with over 75,000 miles on the odometer.


Castrol® GTX® High Mileage 20W-50 is specially formulated for vehicles with over 75,000 miles. It contains Phosphorus Replacement Technology, which reduces the level of phosphorus and replaces it with a proprietary additive that preserves your emission system while maintaining robust wear protection. Castrol® GTX® 20W-50 is formulated to clean away existing sludge while preventing new sludge formation to help extend engine life. It is also liquid engineered to resist viscosity and thermal breakdown.

* When tested in engines with a high level of deposits