In recent years, many vehicle manufacturers have extended their engine oil change service intervals. There are several reasons for this:
1) Modern engine oils offer superior lubrication.
2) Environmental concerns about waste oil.
3) Many manufacturers are offering no cost maintenance when the car is new, and that now makes oil services an expense to them.
While modern technology has brought us superior oils, it has also created very high tech engines featuring dual overhead camshafts run by timing chains, four or more valves per cylinder, and low tension piston rings, all built with very tight clearances.
Twenty years ago, these features would have only been found in a Ferrari or Lamborghini!
The consequence of not changing your oil frequently enough can be devastating to many of these modern engines: miss one oil change and you could eventually be in for very expensive repairs.
Some European cars feature very long oil change intervals: as high as 25,000 kilometers. I can say from personal experience that oil with that mileage on it is very contaminated and definitely not as effective as it should be. What happens in many engines, when oil is left too long is sludge build up occurs. The sludge will eventually block oil passageways and starve components of lubricant, causing them to wear quickly.
After undertaking intense technical research I have found that there is a huge variance of opinion amongst the experts: some say that changing oil every 10,000 kilometers is just fine while others state that anything over 5,000 kilometers can cause accelerated engine wear. In my own experience, along with the information that I have gathered, there are some engines which can tolerate long oil change intervals and still operate fine: they can in fact handle abuse.
Other engines however cannot tolerate any abuse and will die an early and expensive death.
As cars are always changing, with new engine designs continually being introduced, how does one know which engine can take abuse? You don’t: so unless you want to experiment and perhaps end up spending a great deal of money… it is best to keep oil change intervals at around 5,000km for most cars.
The exception – some with large capacities and synthetic oil can go longer.