How to fix a oil leak
4 Answers
It all depends on where it is leaking from. Can you tell us from where? The oil plug, filter, gasket, etc?
You may not have gotten all the old oil filter gasket off when you replaced the filter. Sometimes the old filter gasket sticks to the mounting surface and prevent the new one from sealing.
Like Ken said, remove the filter to see if you have two gaskets there. You might also just need to tighten the new filter. It doesn't need to be torqued down, all that is required is a good hand tightening and maybe a quarter turn with a wrench. Did you rub some new oil on the gasket before installing? You should always do that to help it seal.