I bought a lube-locker gasket for my diffs when I lived in Florida to make it easier to change the fluid in case some water got in after deeper water wheeling. You can change the fluid quite a few times before you need to replace the lube-locker gasket but it might not be worth it to you if you don't normally go through deeper water. Grey RTV works really good too, I just got tired of prying the cover off and having to scrape it clean.