[Darren69]

Yes, hello and welcome to monsterdom. You'll find a few nuts on here, some cracked, some not and some probably about to at anytime soon.

I seem to recall someone on here some time ago, with more engineering skills and equipment than me was making replacement fuel sender nuts to order. Not cheap but then again low volume bespoke stuff never can be. I was going to order one but I checked mine ('02 S4) and it already was metal. I think they changed to metal at the factory around that time for the same reasons, but I'm not sure if you can buy the nut without the expensive sender unit, that maybe the fly in ointment but worth checking and also ebay for anything s/hand post '02 as it will probably fit. But as Gazza says go easy with the plastic one otherwise it will crack!