Which oil do I need for my k12?

[KBM]

Sorry this might be a silly question and have been done a lot but still not sure. Checked the dipstick on my 2008 k12 and looks like I might need to top up the oil soon. The manual says 5w30 but should I go semi synthetic or fully synthetic? (I don’t know what’s in the car already) Some people seem to use 10w40 also (I did in my previous 2004 model as a mech recommended it at the time so not sure what’s best) As I don’t know what’s in the car would it matter if what I put in was different to what’s already in it and they mixed. Any particular brand any good? Thanks

 

[WightK12]

The lower figure (5) relates to cold weather performance the higher one for warm weather . 10w40 would be fine as to which one , the best you can afford up to Mobil 1 and do a full change.
I would use semi-synthetic as a minimum but use full synth on all my cars and bikes.

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