There’s a trend these days to longer recommended service intervals. 15,000km is not unusual, with some makers even stretching to 20,000km.
RACQ technical staff are now seeing an increasing number of engines taht have sludged up the fine oil galleries inside them, to the point where the vital lubricating oil can no longer circulate.
Expensive damage results.
A bit like blocked arteries in the human body really, and it’s just as terminal for your car’s engine.
Look carefully at the owner’s handbook. Most will recommend an oil change more frequently, around 5000km if the vehicle is used under “severe conditions”, to prevent sludge forming. Typical city use is one of hte operating conditions defined as “severe”.
So don’t neglect your engine’s health. Oil is cheap, engines aren’t.