Hi Harry, Many times I have found that you can use a heat gun, or hair dryer, and lift the paper label to reveal the back bearing of these bans. A shot of an oil such as Triflow (teflon and oil lubricant) will quieten the fan for several more years. It just takes a tiny drop of lubricant. Be sure to use a true lube oil, not WD 40 or other water displacing spray. 73 and GL, Stuart K5KVH