After losing oil for the last 6 months( not leaking) I switched from 5w20 to 5w 30 synthetic ( per recommendations on this forum). In the process I spilled a few oz's of oil on the engine. I wiped it up as much as possible and expected some drips for a couple of days. I crawled under and wiped the bottom of the engine yesterday and it looked like there was a leak. Could changing oil weight cause a leak to develop, or am I just seeing residual dripping from spilled oil?