In theory they should be replaced every time. In reality you can probably get away with using it a few times. But when you reuse you run the risk of needing to tighten the drain plug a little more so no leak. And of course possible stripping the threads in the oil pan.
I have some drain plug washers that were metal towards the outside and rubber towards the inside. I like them.
These days I have a Fumoto valve in one vehicle and the drain plug in my PSD has a o-ring.
I have some drain plug washers that were metal towards the outside and rubber towards the inside. I like them.
These days I have a Fumoto valve in one vehicle and the drain plug in my PSD has a o-ring.