Could you elaborate on the "failure"? Many people think that an alternator's failure is the bearings. And, that CAN be the case, at times. However, MY alternator died not as a result of the alternator bearings, but the diode rectifiers. It was not a condition of pass/fail, but that it was only putting out 12.4 volts. And, would not keep the battery charged.
Personally, I would NEVER use a factory alt. The reason is that I spoke with a guy who suppies OEM! He told me that while Ford COULD use the best stuff, he said they shoot them a price point. Then, to meet that price point, they are required to make it cheap. He said that he warned them, it would not last beyond 100K miles. They were happy with that, because they only warranty to 36K. And, if it saves them $50/ea, over 800K vehicles....do the math.
Anyway, I went with a DC Power alt. It is built to withstand HARSH use. And, you can get them in either factory output, high output, or ultra high output. They are priced accordingly, but the factory output is priced very near the OEM replacement cost! 2 year guarantee, as well.
