Need dual battery help

[dcofer]

I have a 2011 Silverado 1500 and I am in the process of trying to install a second battery (XS Power). The problem I am running in to is that I can not find a switched 12v source to control my isolation relay in the engine compartment.

This is starting to get frustrating as you can imagine. I understand the theory that the batteries can drain each other if not isolated when the truck is off but have no practical experience with this.

is it safe to run the second battery without an isolator? or does anyone know where to get an on run 12v source?

Also I am using the stock battery and adding the XS, not dual XS.

Thanks

Edit: this is also not a daily driver and can sometimes sit for a few days without use if that helps.

[Rmichael91]

You don't NEED an isolator. You'd only need one if you were going to run your system for periods of time with the truck off so your starting battery can still crank the truck and not drain. If you still want to use it, try using the windshield wiper, fog/headlights fuses

[dcofer]

yeah im not an idle bumper so it would be pretty safe in those regards.

Ill do some more checking i nthe fuse box.

my biggest concern is the batteries trying to equalize when its off but i feel I am being overly cautious about this issue.

Thanks for the reply.

[Miguels]

You don't NEED an isolator. You'd only need one if you were going to run your system for periods of time with the truck off so your starting battery can still crank the truck and not drain. If you still want to use it, try using the windshield wiper, fog/headlights fuses

and i still wouldnt recommend to play music with the car off even if you have an isolator.. playing music with car off drains battery and will damage your alternator if you try and charge them up with it. never play with car off. if you do recharge them before you turn your car on

[Rmichael91]

You don't NEED an isolator. You'd only need one if you were going to run your system for periods of time with the truck off so your starting battery can still crank the truck and not drain. If you still want to use it, try using the windshield wiper, fog/headlights fuses

and i still wouldnt recommend to play music with the car off even if you have an isolator.. playing music with car off drains battery and will damage your alternator if you try and charge them up with it. never play with car off. if you do recharge them before you turn your car on

I don't recommend it either. I just hit the point the OP was stuck on.

[bbeljefe]

You won't damage an alternator from charging a low battery. If that much draw would harm it, it would be killed every time your system hit a hard, long bass note.

Alternator damage can occur from boosting another vehicle when yours is running but not from charging a low battery.

As for battery isolators, OP... you don't need one from what you're saying. And, the batteries won't drain one another. The wet cell battery has a lower surface charge than the AGM (less than a volt difference) and will seek to maintain its surface charge until the AGM is drained to its level. After that, there will be no more battery drain unless you have something causing a constant current draw on your electrical system.