I’ll actually push back a bit on the lifetime washer thing—had better luck with them than the cheap ones, but only when I’m careful about matching sizes and cleaning the mating surfaces. Most failures I see in my units are from folks mixing old and new parts or skipping the prep work. The blue silicone ones are hit or miss, though. In rentals with hard water, I’ve switched to PTFE tape plus a fiber washer, seems to last longer and less prone to shifting. Hard water really chews through some of the softer materials...
Most failures I see in my units are from folks mixing old and new parts or skipping the prep work.
Yeah, skipping the cleaning step is a killer. I’ve seen leaks pop up just from a tiny bit of grit left behind. I’m with you on the blue silicone washers too—sometimes they seal great, sometimes they just squish out of place. Hard water’s brutal on everything, honestly. PTFE tape plus fiber washer is a solid combo, especially if you’re dealing with tenants who aren’t gentle with fixtures.