Yesterday I was towing with my 95 Z71 and when I stopped at a light, I looked at the battery gauge. The needle was going back and forth in time with the turn signal. It was only a couple of marks back and forth, but I have never seen this before. What would cause this? I just had the alternator tested and it was okay; the battery is pretty new. Could the alternator be okay for regular use but not strong enough when the trailer is plugged in? It is the original alternator. Thanks!

 

That's caused by an "iffy" ground to the instrument cluster. Check all your body grounds.

Allan

 

Just a suggestion, make sure you have a seperate ground wire from the trailer wiring to the vehicle, the ball mount is not a perfect ground. Good luck and travel safe.
david

 

Thank you for your help! I just had to have the truck's wiring repaired and a new plug put in for the trailer. He wasn't sure exactly what I needed since the trailer wasn't there. He asked me some questions about the ground wire, but I had no clue. Guess I will run it back up there this weekend!