Oil question

[76bonanza]

The previous owner ran 20w50 castrol synthblend so I ran it at my last change, but this change I would like to run 10w40 same castrol synthblend.

I dont mind the brand just 20w50 seems so thick.

My question is do you think it might leak worse going to a lighter blend? It leaks a very small amount now not even enuf to drip on the ground I never have to add oil at all between changes which is about 4-5 months 1500-2000 miles I only drive it about 15 miles a day to work.

Thanks for any thoughts.