Grohe Ladylux Faucet leaking after 11 years
I never heard of that brand. But then again I’ve been working with plumbing for just a few years. However your right on your thoughts. Depending on how Grohe Ladylux faucets are built it’ll be either the o ring or the cartidge. Always check o ring first because it is way cheaper to fix than cartidge. But if you need to, take the old one out and go to your closest home improvement store to match the correct size. If that’s not it, also look at their cartidges at the store. If you have no luck there, try and contact Grohe company themselves. If they are like Delta or Moen they have a lifetime warranty and can probably get you a replacement part. If you have no luck with Grohe or the home improvement store(s). Then I’d recommend Danco. Danco makes replacement parts for faucets and they might have the cartidge your looking for. It’s a big hassle because cartridges/stems are very VERY brand specific. Hopefully it won’t cost you a leg and a arm. If the price is around $50 or more, I’d just recommend a new kitchen faucet.