i use fuchs 10w 40semi stuff every 5k with a new filter. car runs sweet as a nut and sounds perfect. i aggree that the expensive stuff (castrol gtx etc) is a waste of money! unless you dont do your oil changes for 20k periods, otherwise you are wasting money, cheapo oil breaks down at around 7k, semi stuff lasts alot longer and fully synth oil lasts for 20k+ miles, so- if you are filling your car up with really expensive fully synth oil every week then stop 😃 lol
just my 2 pence worth!