Outdoor Power Equipment and Small Engines - Changing lawn mower oil before winter

I have always run a whole season on my lawn mower oil and changed it after the last cutting. The oil was always pretty dirty so this summer I changed it in August. I was going to change it again last week but it looked pretty clean on the dipstick and on my finger. I probably cut the lawn 10 times since the oil was changed.

Should I change it even though it looks clean? I know there must be some contaminants in it but nothing like it would have been had I not changed it a couple months ago.

I would....... like you said it might look clean, but can still be broken down by heat, contaminents, etc. As cheap as an oil change is why chance it? That way it'll be ready for next season. Later!