Dual battery help!

[mcgml]

I have a dual battery setup on my 2005 5.3 v8 1500. I am new to the forum scene and looking for guidance. I have interesting voltage climb and drop and would like someone with more experience to help me out if possible I am attaching a diagram of setup ( I’m no artist) 

[mcgml]

Side note... Im not sure if this is the proper spot to post this topic. Still trynna figure this whole scene out. gotta love some new guys coming in to ruin things. 

[Aaaaaaaayush]

What exactly are you getting voltage drop across?

 

[mcgml]

Im not sure I understand what you are asking? would you mind clarifying? My batteries read as they should disconnected and connected with the ml-acr. When I drive around with my subs and amp running I do notice some drops in voltage on average between 12.5v-15.1v when at idle ill hit high 14v"s - 15v. When driving I see an average of 12.5v-13.1v. on occasion I've seen it hit 11.5v's coming to a stop then it kicks right back up.

update as well. contacted mechman and was told to add a dedicated positive lead off the alt to batt. Also added a ground straight from alt mounting bolt to rvc to batt. They also told me to take the factory ground and terminate it at the alt ground as well.