Battery light comes on at about 4000 rpm
Battery light comes on at about 4000 rpm
Battery light comes on at about 4000 rpm, regardless of load or accelerator position or gear.
Most likely cause? Alternator?
Battery is less than a year old, belt is not slipping.
Most likely cause? Alternator?
Battery is less than a year old, belt is not slipping.
I plugged a DVM into the lighter socket this morning and took it out for a drive - it's running at 13.96 volts. When the battery light comes on, it drops to 12.1. That's undervoltage, not overvoltage. Still think it's the alternator?
It might be... remember my taunting thread about my insane alternator/pulley problem? I'd say replace it.
Get a NAPA "new" alternator... it's got a 3 year warranty on it, plus the design of the alternator is much better than the Motorcraft one, especially under heavy draw. There is no whine.
Get a NAPA "new" alternator... it's got a 3 year warranty on it, plus the design of the alternator is much better than the Motorcraft one, especially under heavy draw. There is no whine.
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It might be... remember my taunting thread about my insane alternator/pulley problem? I'd say replace it.
Get a NAPA "new" alternator... it's got a 3 year warranty on it, plus the design of the alternator is much better than the Motorcraft one, especially under heavy draw. There is no whine.
Get a NAPA "new" alternator... it's got a 3 year warranty on it, plus the design of the alternator is much better than the Motorcraft one, especially under heavy draw. There is no whine.

Wow, you let a dealership work on your truck? I never thought I'd see the day
I don't do my own work any more. The dealer here is excellent and reasonable - $79.85/hr labor. I don't use them for stuff that independents can't screw up like oil changes, exhaust, shocks, brakes, and tires though. I go to specialists for that stuff.
WDS, reman alternator, labor, tax - $340.
WDS, reman alternator, labor, tax - $340.
I don't do my own work any more. The dealer here is excellent and reasonable - $79.85/hr labor. I don't use them for stuff that independents can't screw up like oil changes, exhaust, shocks, brakes, and tires though. I go to specialists for that stuff.
WDS, reman alternator, labor, tax - $340.
WDS, reman alternator, labor, tax - $340.
generators in ford terms are suppose to put out 13 plus anything below and its time to replace however anything over 15 its over charging and yes you can have a bad new generator i have seen it ( under any load it has to charge between these levels ). they are not hard to change but i do recommend motocraft brand not cause i am a tech but i have had people come in with a new generator installed and it was bad or went bad very quickly
Last edited by streetracer1232; Jul 2, 2010 at 02:02 PM.
generators in ford terms are suppose to put out 13 plus anything below and its time to replace however anything over 15 its over charging and yes you can have a bad new generator i have seen it ( under any load it has to charge between these levels ). they are not hard to change but i do recommend motocraft brand not cause i am a tech but i have had people come in with a new generator installed and it was bad or went bad very quickly






