Two bearings in the column...one at the top by the wheel, and one down by the rag joint end. Rarely have problems with them, but they can get dry over the years, and create noises, and binds when they have no grease. If they're that bad, you should be able to feel some up/down side/side play in the shaft.
The upper bearing can be serviced/replaced without removing the column, but the lower bearing requires column removal and dis-assembly to replace. Neither is an especially pleasant job....
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Joel Adams
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