I was reading the service manual of Audi Q3 and was surprised to know the recommended oil change interval of new car is 30000 kms or 730 days. Compare this to a suzuki sedan or even a hatch that recommends to change the engine oil after 10000 kms or 6 months.Even a 100 cc commuter bike it is recommended to change the oil after 4000 kms or 4 months. I am just curious to know how a 2.0L SUV has such a very long oil change interval compared to a bike
I have an Audi 3.0 TDI 2010 and have been driving it less than 10K kilometers a year (working from home, wife has a car and so on). I have been to service every two years, which made me worry about the state of oil.
So I asked the service if I should consider more frequent oil change. They said that the car will automatically adjust service interval based on cold starts, time and distance driven. Meaning that it will probably be 30K interval if you cover that distance in less than 2 years. For me the actual oli change interval has turned out something around 20K kilometers.
As of why this is possible - I guess the modern synthetic oil lasts longer. I also suspect that this applies until the engine is in good shape. After 300-400 thousand kilometers the conditions inside the engine may change.
It is most likely that the oil originally fitted, and most probably specified in the manual, is a higher grade than the oil suggested for the other examples you gave. The filter may also be larger...
The oil specified for my car is a grade not available in most "cheap" stores but is available easily at the dealer and higher quality stores...
Many newer cars are suggesting longer intervals between changes. This is mostly due to the use of full synthetic oils with long-life additives, and just generally cleaner-running engines. For example, my 2008 MINI Cooper has a suggested 15k mile/1 year interval. Follow the manufacturer's specifications for oil and filter.
One thing to check regularly is the oil level. Just because you only need an oil/filter change every 2 years doesn't mean that the car won't consume some of that oil. Make a habit of checking the dipstick every month and top it up if needed.