OK just to put the two cents in of a high voltage electrician that has experience in rebuilding full size (500kw-1.5MW) generators. A rebuilt alternator is as good if not better than the OEM. If a componet is found to be a common failure, by a major rebuilder, it is usally up graded to a new more reliable part. Also, the windings are usally revarnished and baked, this thickens the insulation on the windings and repairs the week or faulty areas. And on top of this the bearings are replaced. Most alternators that go bad in the first part of their life is usaly due to over tightening the belt cuasing overheating. Next is due to poor reman process. So do not buy the bargan brand. I have never had an issue buying a rebuilt alternator. I have seen a couple go bad or shipped bad, but for the money savings over buying new there is not a better option. Except for junk yard $12 dollar replacements.