Join Date: Dec 2013
Location: Puget Sound, and Allegheny County (PA)
I've spent more time thinking about that blasted crush washer than it's worth and have never been able to think of how (or why) a new crush washer, once crushed, is any different, (let alone better), than an already crushed washer reinstalled and brought to the same compressed state as it had when initially crushed. I figure there is still some spring in it, but even if not it is soft enough to get the sealing job done.
Mine was replaced at 600 miles because it was in the shop, but in the 10+ oil changes since, the same one goes back, still conveniently on the plug, because it looks fine. I've never had a hint of leakage from the plug.
Replacing gaskets, as a rule, is a good idea because they get damaged or shift. But my oil plug crush washer is as good as new, and it certainly does not shift. The surfaces between which it seals are so flat that I doubt the crushing effect matters. Any soft material would be fine there.