Basically u need to keep few things in mind for an engine oil. In Pakistan stick to a company which has good reputation and provides quality oil. Then there are 3 types of oil, Standard Oil, Semi Senthetic Oil and Full Senthetic Oil. The main difference is types of additives used in these oil. Generally Standard Oil r advised to be changes at 5000km, Semi Synthetic at 7000km and Fully Senthetic at 10,000km. Full syth r ideal for brand new cars, semi synt good for used cars with good engine condition which does not consume oil. Remember u engine sounds really smooth when u use fully senthetic.
Another difference is in the cold start up. A standard oil luricates engine in 45 seconds, semi syth in 15 secs and fully sent in 4 secs, hence synthetic oil provides better protection as max damage to the engine is done at the start up. I have been using a fully syth oil and Im a great fan of it, not sure if it will work equally well with an old engine.
I returned to Pak after 10 yrs and not very familiar with the brands here and u guys have educated me by ur inputs. I used Mobile 1 which was good but the best was fully synth by TOTAL and no oil could match its performance. Im not sure if TOTAL has the same quality here but I guess foreign brands r better and its worth spending that extra bit towards ur car.
U should import Slick 50 from UK, its an amazing treatment for an engine and I used it in my Margalla long time back (when genuine Slick 50 was avail) and the engine went very quiet and smooth. Dont buy it from Pakistan as genuine Slick 50 r not availble here and people who used it were pretty dissapointed as their cars started to consume oil and they had to get the engine flushed to get rid of the problem as it created loads to carbon in the engine.
Any useful suggestion, plz feel free to comment