Wiring dual batteries. Help please.

[Lbetts818]

Wiring has never been my strong point but to save coin for more gear going to try it my self. Sorry if this is a repeated question. About to run my 2nd battery and was curious if run a wire from front pos to rear pos and front neg to rear neg do I have to ground rear neg on the battery to the chassis still. Or can I just hook my amps negatives and positives to the pos and neg on the rear battery and be done? Or do I still need to find a spot on the car to ground rear battery also? I would fuse each long run front and back and each pos to amp. Is this right? Any info would be appreciated. Trying the diy way this time so I can saw some money and learn at the same time.

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[wew lad 5,000+ posts]

Ideally you'll run a ~4 to 1/0 positive and negative run to the rear battery from the front battery and then a short run of pos/neg to your amp. i would also add a ground from the battery to the chassis and upgrade the ground and power wires to your alternator and battery.

you'll fuse only the positive run from the front to the back, and then fuse again from the battery to the amp. ideally, it's safest if you fuse the positive run from the front battery to the rear battery twice. one fuse within 12-18 inches of each + battery terminal because they're both sources of power.

 

[Lbetts818]

Ideally you'll run a ~4 to 1/0 positive and negative run to the rear battery from the front battery and then a short run of pos/neg to your amp. i would also add a ground from the battery to the chassis and upgrade the ground and power wires to your alternator and battery.
you'll fuse only the positive run from the front to the back, and then fuse again from the battery to the amp. ideally, it's safest if you fuse the positive run from the front battery to the rear battery twice. one fuse within 12-18 inches of each + battery terminal because they're both sources of power.

Game plan is one run of 2/0 welding cable from front to back for each pos and neg run. Wasn't sure if second battery needed to be grounded also to something in the rear or if it was ok being grounded to the front batt. In Michigan here grounding to the actual vehicle frame seems pointless since rust and what not so will find a good spot in the truck somewhere. And yes big three is the first thing getting done //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif thanks for the info.

 

[Hertz Mafia]

Game plan is one run of 2/0 welding cable from front to back for each pos and neg run. Wasn't sure if second battery needed to be grounded also to something in the rear or if it was ok being grounded to the front batt. In Michigan here grounding to the actual vehicle frame seems pointless since rust and what not so will find a good spot in the truck somewhere. And yes big three is the first thing getting done //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif thanks for the info.

Ground back battery to front battery.. ground amps to rear batt. I already told you this . If u don't want to have a NEG run front to back then ground the batts in the rear.

 

[Lbetts818]

Will do. Sorry hertz. That's what I could've swore you said but didn't wanna keep bugging you with the noobish questions //content.invisioncic.com/y282845/emoticons/frown.gif.a3531fa0534503350665a1e957861287.gif That's what I was going to do was like you said but someone said ground rear batt also to front and chassis so threw me off

 

---------- Post added at 09:00 AM ---------- Previous post was at 08:59 AM ----------

 

I plan on doing runs from both pos and neg from front to back

 

[Hertz Mafia]

Will do. Sorry hertz. That's what I could've swore you said but didn't wanna keep bugging you with the noobish questions //content.invisioncic.com/y282845/emoticons/frown.gif.a3531fa0534503350665a1e957861287.gif That's what I was going to do was like you said but someone said ground rear batt also to front and chassis so threw me off 

---------- Post added at 09:00 AM ---------- Previous post was at 08:59 AM ----------

 

I plan on doing runs from both pos and neg from front to back

Yea runs front to back... then ground your front battery to your engine block/frame...aka do big three up there

 

[Lbetts818]

Yea runs front to back... then ground your front battery to your engine block/frame...aka do big three up there

So big three and runs each. No need to ground rear batt to anything extra correct? And then 4 channel and cab 1600 to rear batt. Done. Correct? Thank you

 

[Hertz Mafia]

Just upgrade power wire from

alt to front batt

Front batt ground to engine block

Then run your power and neg run to the back batt

Ground amps to back batt