Are you greasing it with volvo grease?? Mine dripped when I bought the boat as PO was not greasing it. Get a plastic straw squirt grease into it flatten it out ,insert under seal and squeeze in the grease.The next haulout I pulled the shaft put it in a lathe and polished it with 1000 grit ,new volvo seal and grease , I also add a skf forsheda seal in front on the shaft giving 3 sealing surfaces. Mine had a good groove from no grease so I added a flex coupling moving the shaft onto a new surface. Use only volvo grease as other types may harden rubber . Greased every year or 200 hrs and it should not drip for 7 to 10 years. My buddys leaked bad so he put a stainless clamp around it tighten it up after greasing, no leaks for 2 years ,then changed it