Whatever oil you use, it's best we replace every 5,000km or 3 months whichever comes 1st.

My opinions on the 5,000km or 3 months policy comes from the different type of comsumers & cars that they own;

- nice performance NA or turbo car & owners who has budget irrespective of driving habits; re-commend synthetic oil as they will have an excuse to visit the workshop more frequently which they do not mind. I have seen these type of ppl changing their synthetic oil every month with mileage less than 3,000km as they 'feel' their car has better responce right after the oil change which I believe in true.

- nice performance NA or turbo car & owners who usually 'whacks' the car only use synthetic oil.

- normal passenger comfort cars less tha 3 yrs old whose owner alternate between synthetic & semi-synthetic oil as they believe to understand the extra reliability that comes with frequent 'servicing'.

- speed freaks with modified cars NA or turbo with average budget using semi-syn, 10/30 oil or 15/50 oil.

- not to mention our average Joe's car who comes in routinely for their 5,000km service using 15/50 or 20/50 oil. Their opinions are that all the engine oil is the same & engine reliability issues is all because of the 'bad' villian mechanic.

- no comment on the BMW little green light theory on dashboard as even the syn oil you thrash for more than 10,000km also still indicate oil still in good condition(on a friends M3) , my recommendation is otherwise of course.

This post has been edited by MobyDick: Oct 8 2008, 02:31 PM

If your existing engine since new has been run-in more than 10K km with a specific engine oil viscosity, I'd suggest you stick to the similar one but if you wanna try a lighter one maybe to improve FC & engine responsiveness, than can try switching to the Kancil 10/30 ones or maybe to full-syn if you're already on 10/30. If there aren't any serious oil losses(say less than 250ml) after 5K km, than can continue using it.

Take note that once a specific engine has been optimumly run-in to its relative 'oil-gap' between piston/rings & engine sleeve, there's no point in goin for a lighter viscocity oil unless you do not mind the frequent top-ups within your schedule service intervals.