2006 Toyota Tundra V8 voltage display surges

Hey, I have a 2006 Toyota Tundra v8 - on the instrument cluster, the battery voltage display surges occasionally. AC fan and lights for the vehicle also surges when this happens.
Did a little test;
- when its stable, with the engine running i remove both positive and negative cables from the battery - the truck continues to run with no problem.
- when its surging, with the engine running - it shuts off when i remove the cables.
Cables at the battery terminals were all checked for tightness and proper contact.

Does this indicate that my alternator is malfunctioning and i should replace before failure?
Should I have another test done? Any recommendations?

 

Double check body grounds for good connection. Take them off and clean the surfaces bare and apply some dielectric grease to the connections. You can swing by the local VatoZone or your favorite car parts box store and have them check your alternator for you.

 

thanks for the feedback - hope this helps. will keep you posted.

 

Sound like your voltage regulator in your alternator is about to take a dump.