My 6600 started clanking and squeaking which prompted me to come crying to the QB. I was told in no uncertain terms, especially by one who PM'd me, lol, that my machine needed to be oiled and pronto! Went to WalMart, the closest place to me and bought Singer sewing machine oil. I ended up having to put 3 drops of oil in there. It was dry as a bone. Since then, it's purring right along. It's time for the yearly maintenance, but I have soooo many projects going and just don't have time to get it done right now.