Originally Posted by KallyI
Thanks for all your replies. I purchased the alternator at Napa 2 years ago in August, so it was still under warranty. We can't get a lifetime warranty from Napa here in Canada. They gave me a replacement, which has a 3 year warranty, and all seems good now. The voltage does fluctuate more than the previous alternators did, so I'll keep an eye on it, but I do have my tach reading back :) . Does anyone have any idea why these trucks of ours seem to eat alternators? The original alternator failed and was rebuilt in 2001, at about 75,000 miles, then it failed again in 2004, with about 130,000 miles, to be replaced with a Napa unit, and now with about 150,000 miles. That just seems excessive to me.