I had replaced mine a decade ago with a magnetic drain plug...pulled out the box of originals from all my cars and there's several washers in there but don't know what went with what, some washers in the box aren't originals... So did the original allen head drain bolt have a washer also on it or no washer??? (I installed with what looked to be a factory washer of some sort with the rubber ring inside and its leaking like a sieve...)
Yep it do use a gasket ... the style metal with rubbery edge on the inside to seal properly ... don't have the part number handy as I'm on the road this week. You might like to know we have a company ready to replicate the OEM drain plug in stainless steel and we will get them to cut a pocket at the top for us that like to glue a magnet in place as well .... they are a bit busy at the moment for the next 3 month but at that point we can get these done and it wont cost too much.
OK, I think I have a few others with the rubber inside, that is a fairly popular design. The magnetic one I had on there was extremely low profile, the head was a hex bolt, but was barely thick enough to get the socket on it, I had a socket I sanded the edge down since the socket sides were slightly recessed.
