I was dealing with an AquaClear rattle and replaced the impeller on their advice, but I was still getting the same noise. Turns out that I likely have a failing shaft. After looking for solutions, I applied silicone grease and that seems to have helped but I'm thinking I have only delayed a possible motor/shaft replacement. I'm wondering if I should start using silicone grease from the start next time. Any chance that might prevent or at least delay the shaft failure?