I have a 1996 Acura Integra with manual transmission. It has only 113K miles on it. I put on only 6K to 7.5K miles a year. I have owned the car since it was new & have always changed the oil & oil filter myself. Until about 3 years ago I changed the oil & filter 4 times a year–roughly about every 2K miles. Three years ago I reduced the number of oil changes to 3 times per year. Recently it was suggested to me that even that was too many and that I should change the oil & filter every 6 months. To be honest I am not comfortable with that but I also realize that my discomfort may simply come from habit. I have changed the oil & filter every 2K on every car that I have owned since I was a teenager. I should tell you that I am 80 years old and live on my savings & a pension. To replace this car would cost me between $25K to $30K so it is to my advantage to keep the car on the road for as long as I can. In short will I be doing any harm to the engine by changing the oil every 6 months?
A second question that I have about oil is that it is becoming increasingly more & more difficult to buy a high quality brand of conventional motor oil. When I shop I have been finding that the better engine oils, Castrol GTX, for example, do not offer much of a selection when it comes to conventional motor oil. In fact conventional motor oil is their cheapest oil. Most of the varieties of oil that they offer are blends of conventional motor oil & synthetic oil. I have heard conflicting statements about switching from conventional oil to synthetic oil. Some say it is dangerous to do and that it should not be done while others say that it does no harm. But what about switching to a blend of conventional oil & synthetic oil? Will that cause any damage to the engine? Thank you for your help.