UK Car Repair: Change of oil grade, vauxhall astra, grade oils

Question
Hi, I have a Vauxhall Astra 1.6 8v and have been using 10w 40 oil in it since new. The car has now done 110000 miles and I was wondering if I should change the grade of oil and if so, to what type?

Answer
It depends on your climate. Generally an older car can use a higher grade oil so you could likely move to a 20/50. I personally use straight grade Oils.  I am in a hot climate so in winter I use a 30 grade and in summer 40. I find single grade oils are better than the "compromised" mixed grades.