Car-owner handbooks will give you a minimum oil specification. However, you may wish to trade up to a better specification engine oil. Choosing the correct engine oil for a vehicle depends on:

• the car’s type – a high-performance car needs higher performance oil.
• the car’s age – a lot is expected from new technology engines: high performance coupled with fuel efficiency. Advanced oils have been developed to help keep pace with increased engineering demands. For example, modern cars have blow-by-gas recirculation that can cause extreme oxidation in old-technology oils and sensitive exhaust gas after-treatment devices that can be poisoned by inappropriate oils.
• the driving environment – modern motorway driving and heavy stop-start traffic requires higher quality oils to prevent increased engine wear and tear.