What is important is the quality of the oil. A very good mineral oil is better than an inferior synthetic that does not meet lubricity, sheer, surfactant, and soot control specifications.
What have you been using up until now? And has it been consistent with every oil change? If you were concerned, go 5W-40 in the winter and 10W-40 in the summer. I live in FNQ tropics where it is warmer most of the time, so I run Penrite 10W-40 extra 10. It is recommended where 10W-30 is also used. Plus is what is recommended by the suitability website. What does the manufacturer state to use? Here is an oil chart.