I know. So what do u recommend? Except for the 1st few oil changes, had always been using Caltex Havoline 20w50. Thinking of switching then learned from different sources that :-
1. Oil grade/brand shouldn't be switched abrubtly specially after this much running of car.
2. 20w50 is actually considered good for old engines to take care of any already worn out or suspected wearing out of engine parts by providing a good seal effect.