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  5. Synthetic blend oil

Synthetic blend oil

Synthetic blend motor oil combines affordability with enhanced protection. Learn how part synthetic fluids can benefit your engine.

Castrol® Synthetic Blend motor oil

What is synthetic blend oil?

What is part synthetic oil? Also known as Semi Synthetic or Synthetic Blend engine oil, these motor oils provide a balance between the economy offered by conventional oil and the superior performance of full synthetic oil.

 

Among the leading part synthetic oils you can choose between are Castrol® GTX® Ultraclean, which provides superior protection against the build-up of sludge, and Castrol® GTX® High Mileage, which is engineered for vehicles with over 75,000 miles on the odometer, but that don't require a full synthetic.

Castrol® GTX High Mileage motor oil

Castrol® GTX® High Mileage semi synthetic

Castrol® GTX® High Mileage Motor Oil has been liquid engineered specifically for vehicles with more than 75,000 miles on the odometer. Not only does it protect against sludge, wear and burn-off, it features Phosphorous Replacement Technology to help protect your car's emission system from catalytic converter failure.