i would like to ask ur opinion in engine area. I get a new car last year, from my friend suggestion, he said that i have to change the engine follow by time (for example in three month) but not by my mileage meter...... that mean if i seldom use my car i have to change my engine oil after three month even stil havent reach the oli replacement mileage.....izzit true?? izzit i need to do it this way??i think it is wasted.....if i follow mileage meter to change my engine oil izzit will make bad effect to my car engine if i over the period of using the oil, this is because i seldom run my car.....give me some opinion about it, thank q very much.