do i need a battery isolator

do i need a battery isolator if i use 2 yellow top optima battery's,how should i wire the to battery's together.1 battery is for the truck,and 1 is for the 2 air zenith's...please help

how i did mine is i ran a power wire 4-2gauge wire from the pos terminal comin from my alt to the spare battery then grounded the spare to a chasis ground seems to work good for me havent had any problums in 2 1/2 years.

anyone else plese help.

Originally posted by untamedprez



how i did mine is i ran a power wire 4-2gauge wire from the pos terminal comin from my alt to the spare battery then grounded the spare to a chasis ground seems to work good for me havent had any problums in 2 1/2 years.

Thats the way ive wired up systems with two yellow tops and it seemed to be fine...

I think you really only need an isolator if you plan to run the compressors a LOT w/ the truck off, as long as your running the alternator your fine. The isolator will just ensure you can re-start after playing for a while.

i would DEFINATLY make sure you alternator can handle charing 2 optimas. a hi amp alternator should charge 2 of them, but an isolator wouldnt be a bad idea. they sell them at autozone.

the only thing the isolator will do is keep the back battery from draeing voltage from the first batt. you can just run a 80 amp relay instead and just hook it up with the pressure switch so that way you are only using both batt. when the comressor is on there are other ways to hook it up but that works good from my experience if you have a good alt. it shouldn't matter it will charge both batt.