do i need two more fuses for the extra battery or can i just jump power and ground to the battery, the existing battery in the back already has two fuses just did not know if a needed two more or just jump ground and power to second battery thanks
if the two batteries are right next to eachother its fine. just keep in mind if your in an accident and the wire gets pinched and broken and their isnt a fuse right on the power wire of the battery close to the terminal chances are your going to end up with a fire.
If you jump both the positive and negative, don't ground (to the chassis) the second battery as the potential differences (or voltages) could be... different. In that case, I'd add a second ground from the first battery and connect the two positive terminals. However, if it was me (and it was; this is how I did it), I would just connect the positives of your two rear batteries and ground them both to the chassis.
No you don't need fuses if the batteries are right next to each other.
When running the positive wire from front to back batteries though, it has to be fused at both ends. This is something people often forget, and fusing only one end is completely useless.
yeah the current battery in the back i grounded to the chassis so im good there and they will not neccessarily be right next to each other so i will fuse the power wire when i jump it the idea of a possibly fire does not go over well with me lol