“ For basic engines „
Castrol make a wide range of oils for both petrol and diesel engines. All oils are not the same apparently if you look at your local Halfords there are a wide range for different types of engines, choose carefully and you can better protect your engine. Oil is pretty boring stuff, I used to just get the cheapest I could find. However this is false economy, the better oils cost about £10 a gallon more than the cheapies. These give much more protection to your engine. As they only need to be changed about every year it's a small price to pay. My wife's car does a very low mileage, around 5000 a year. Much of this is made up of very short journeys taking the kids to school etc. Much of the engine wear occurs on starting up, to get the maximum protection from your oil it needs to reach temperature, it takes about 5 miles to get anything like warm. I chose the magnetec oil for basic engines, as the name implies it has a magnetic charge to the oil molecules that supposidly stick to the metal in the engine. This gives protection were it is needed from the start. Take a few minutes choosing your oil next time you buy,go for quality rather than the cheapest price. It really is worth it.