I just installed 2 brand new batteries, and we put it on a charging gauge right after. At the battery, its around 13.6-13.8 volts...then it drops down to 11.volts . Then back up to 13.8v. It almost seems as that click of the engine is when it drops, then back up consistency. When the altenator is tested, it holds 78 amps or so, without even moving. How normal is this?

 

It's prorbably just your grid heaters cycling on and off.

 

perfectly normal. as stated above - just the grid heaters doing there thing. this cycling stops once intake air is up to temp

 

Cool..... Man, my truck starts quick now!