Hi,
Kes - the engine has probably been on Mobil 1 0w-40 from new. Like here in OZ this oil is not always readily available - and when it is it is very expensive too
I would look for Mobil 1 Truck and SUV 5w40 it may be more easily obtainable (it is not sold in OZ)and it is suitable for your car
Regards
Doug