I called, since my alternator was bad. The parts store said it was discharging the battery after I shut the engine off. Based on that diagnosis, they went ahead and ordered the parts they thought I'd need even though I only said I might bring it in. Ordering the parts ahead of time gave me a two day turn-around time instead of several. I dropped my alternator off yesterday afternoon. They called and quoted me (half the price of a replacent, by the way) today. I said do it, and they called me again a couple hours later that it eas done. Fantastic service at a fantastic price. See these guys before you buy a new alternator.