2003 Yukon XL SLT - New battery and alternator. Having issues with volt gauge jumping around.

[cj 1990]

I have a 2003 Yukon XL SLT. Replaced the alternator in March 2024 and the battery last night. The voltage meter has always read 14.5 except when the alternator needed to be replaced. Now it goes from 11 to 14.5. Lights dim and fan slows when I slow down. Anyone else with similar experiences?

 

[Miami-Dade]

@cj 1990 Moved you here from 2021+section.
Welcome from Miami&NYC!

 

[rockola1971]

I have a 2003 Yukon XL SLT. Replaced the alternator in March 2024 and the battery last night. The voltage meter has always read 14.5 except when the alternator needed to be replaced. Now it goes from 11 to 14.5. Lights dim and fan slows when I slow down. Anyone else with similar experiences?

You have a corroded/loose negative battery wire OR another bad alternator OR something pulling a really heavy load on the alternator (Short to ground). Id check the battery cable first. Both ends of it.

 

[Fless]

Welcome from Colorado!