oil change question

[lucer]

I only use Castro 5-W30 HM. in my 2005 Q45 so can i know how often or after how long(km)before this synthetic oil needs changed

[Shahidbaig]

First of all 5W - 30 isnt fully synthetic oil, its semi synthetic oil. You can change it around 6k -7k kms depending on driving style and oil condition. If too much doof doof and load bearing drivng better chnage at 6k km. If most is highway and city driving 7k is fine.

Secondly castrol is good oil, but you get lot of duplicacy here for castrol here. Better go for Mobil 1 from there authorized places. You will love it.