For a long time i believed some of the following,
Seems the story is very different.
The story that you can’t go back to mineral oil if you have used synthetic oil is TRUE for cars that are OLD. New car seal technology has evolved, and you can do that. Even the local agents once they know you ask your mileage pattern and then recommend and have said there is no issues reverting back to mineral oil even if the car has been on synthetic for years. This is is good info for a many who would have brought down cars in recent times due to the reduction in taxes in Sri Lanka. You don’t need to bust on expensive synthetic oil if your 6 month mileage is less than than 5,000km.
While synthetic oils are definitely good, that does not mean mineral oil is bad. Seems like a lot of synthetic oils are created using mineral oils with additives 🙂 though there are few brands such as Mobile that be 100% synthetic. However mineral oils have also evolved and as long as you keep changing the oil at shorter frequencies you should not have any issues. However when cars get older the better lubrication capabilities of the synthetic oil might make sense. However if you are a heavy runner and do 10,000km in less than 3-4 months, going synthetic is better on you as the oil filter cost is high and you are better using the synthetic as its cheaper on the total cost and would also help maintain your engine lifetime. Most modern oils both synthetic and mineral also have additives to help prevent slug (deposits). However it seems some engines such as BMW, AUDI and even a few Toyota engines suffer heavily from this and there are special engine oils for these engines, but most engines don’t have this issue.