Use an insulin hypodermic to inject a few drops of SAE 90 gear oil through the rubber seal and into the ball assembly. This will fix dry sealed ball bearings. If your car has 100,000 miles or more, you bearings are in need of oil replenishment.
You may also have dry ball bearings almost anywhere. If a bearing starts to squeal or looks like it could benefit from oil, inject it as preventive maintenance to save major expense of replacement.
If you have a dry, noisey idler pulley bearing, the bearing is usually well on it's way to being damaged... If you don't mind waiting beside the highway when a suspect bearing is treated in this manner fails, I'm sure that Nomen the megadorker will come and spend the time visiting with you.
These sorts of signs tell us that we have a hurtin' unit... certainly, giving one of these bearings will extend it's life span.... but we have no way of knowing how much.... We can now hear the dice rolling....
For my part, the repair, at my convenience when the noise is first encountered, is much easier to take than sitting alongside the road in God know's what kind of weather (unable to run the car to keep warm) and being late for some important event. My time is too valuable to me to waste my time away from work on breakdowns..... my loving bride is much too important to me for me to risk stranding her along our highways and byways...
OTOH, if anyone feels that they are only worth a "bitch-fix"... go for it.
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