This subject of oil type comes up on a few motoring forums and I suppose it's all down to personal choice . My employer once sent me on an oil monitoring course with Castrol . As we had a large fleet of both HGV's and cars and as Castrol was our oil supplier they suggested that rather than changing engine oil on a basis of mileage where some vehicles covered higher mileage than others , the vehicles should have oil samples taken where Castrol would test it and flag up if a certain vehicle needed a change due to the break down of the lubricant. This type of monitoring saved the company I worked for thousands of pounds over the years. Many years down the line and due mainly to the complexities of modern commercial diesel engines Castrol advised a change onto fully synthetic oil. During this course I enquired about using fully synthetic oil in my Metro GTI ( remember them ?) as the 'K' series that it had was at the time being praised by the motoring press . I was told that semi synthetic 10 / 40 oil was perfectly suited to that engine and that only if the engine was going to be raced / rallied would there be a need for fully synth to be used. I think the comment used was why waste your money on the higher spec oil . During my time working for The London Taxi Company , Morris lubricants were the choice for the Black Cab . Again I asked about the choice of oil for my then MG ZR . Same answer Semi Synth 10/40 .
If you can afford the higher spec oil then ok . My only sticking point with oil is the quality of the brand as I never go for the cheaper supermarket type brand .
John
