Castrol® GTX® High Mileage™ - the #1 High Mileage brand - is a premium synthetic blend motor oil specifically formulated for vehicles with over 75,000 miles.  

Catalytic converter failure is one of the most common – and costliest – problems faced by higher mileage vehicles.  Phosphorus is an industry recognized catalyst poison.  All motor oils contain phosphorus as part of the additive package to help prevent engine wear.  Castrol GTX High Mileage’s advanced formula is specially formulated with less phosphorus than other leading high mileage and conventional oils; which helps prevent catalytic converter and emission system failure.  Castrol GTX High Mileage contains a patented Phosphorus Replacement™ technology that provides unsurpassed protection against sludge, wear and oil burn-off.*

If your vehicle has over 75,000 miles, now is the time to switch to the oil that will help prevent emission system failure and extend vehicle life better than any other conventional or high mileage oil – advanced formula Castrol GTX High Mileage.