Adding extra grounds

I'm going to publicly say this. I've gotten a phone call from another member asking all these questions about ground wire mod and having to add the second ground strip from battery to battery this is NOT REQUIRED nor will you gain NOTHING! Just because W-T has a ham transmitter for his truck and draws large amounts of power. If the main cables are in good condition there will be ZERO drop or very little less than 0.2 volts.

The existing main ground cables going to the block are more that enough. If you do a voltage drop test of your cables your going to find out if you have weak ground cables or positive cables. Anything over 0.2 volts voltage drop is a fail for the cables. This load test is done using the load of the starter. You can remove the fuel pump relay from the PDC and allow for longer cranking periods. 

As for the voltage drop test.

As for charging and the battery temp sensor. There is no need in swapping charge the W-T ground mod back to the drivers battery. The voltage will be THE SAME on both batteries. The battery temp sensor will remain on the driver side battery. If the passenger side battery is going bad regardless of the battery temp sensor the voltage is still the same to both batteries it just the PCM can sense passenger battery condition. The point at which the charge lead is hooked to the passenger battery will not affect the charging ability. What will impact the charging ability is the fact you have either a bad positive cable that is failing (drop > 0.2 volts) or ground cable to the block that is failing (drop > 0.2). Adding an extra ground will not fix this but mask the true issue of the bad  grounds to the block. The largest load is the starter at 700 amps. Second largest is the grid heaters at 195 amps. 

Just like in the photo here I've got eight 6V batteries and in two banks. As you can see I've got a battery temp sensor here only on one of the eight batteries. Regardless of the way I hook up the charge from the hydro generator or the solar it still going to charge the same. If the battery to the left should fail then battery temp sensor will never see it but the battery will still be gassy. You can see the left battery towards the top is the negative and then the right battery towards the bottom is the positive side. Every thing is hooked up with bus bars. No different than our mighty Cummins just I do it with eight batteries instead of two batteries. 

AGAIN... THERE IS NO GAINS TO ADDING A SECOND GROUND BETWEEN BATTERIES.

Cummins block can handle more current than a two ought cable could. Ground should be kept SHORT AS POSSIBLE. Which the factory two cables do this exact function and use the block for the rest.