alternator output voltage

[shendren]

what should this be say with the truck running and the lights on (no air). my alternator is showing about 13. 8v on a sun tester at the local starter shop. is this ok? the guy said it should be about 14. 2v. he said my nippon denso alternator is a very good one and that it should last about 150k miles but he thinks this is a little short on voltage output. thanks. scott.

 

[Gary - K7GLD]

Dunno about the newer trucks - haven't measured the output on my new '02 - but my '91 puts out over 15 volts at cruising RPM...