I went to buy my 20/50 from north Oxford BMW and they tried to sell me 15/40 semi synthetic saying that is what I should use... That confused me for a while, but I decided to stick to what has been recommended here. So far so good, no sign of leakage yet so it's seems my panic was not called for!

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However, there is a new concern

...Sorry everyone, it seems as quickly as you solve my problems I'm finding new ones... Well, this time the problem is, under heavy braking there is an electronic sounding beep noise, not too dissimilar to the sound when you turn the ignition on. It doesn't happen every time so it's been hard to work out if it's happening when applying front or back brakes. I had a check of the brakes and the front brake pads (the outside pad of the R/H, and on the inside of the L/H) move when turning the wheel from one direction to the other. Is this supposed to happen? It doesn't seem right to me, but what would I know, I panic when the wheels go round