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Alternator swap issue

Cory Warburton

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After recently swapping out my alternator, my truck lights are slightly dimming repeatedly. It's especially noticeable when I turn on the dome lights. Is it a grounding issue? The alternator doesn't physically touch the metallic base at all, but seems to be grounded only via the two bolts that hold it up and in it's right place. Should I take it off and sand any metal that connects from the bolts to the alternator?

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