Adding a second battery to 2011 Chevy/GMC 1500 is an easy DIY project

Inverters, coolers, radios, warning strobes, laptops, battery chargers, printers and other vital accessories put a huge drainpipe on any type of pickup’s stock electrical mechanism as soon as the truck is sitting on a jobwebsite with the engine off.

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Even via the engine running the amp load essential to power such an variety of accessories can put a strain on the stock electric device.

Add a plow, connect to a weak trailer battery or flip on auxiliary driving, fog or occupational lights and the battery is going to take a hard hit.

In preparation for adding an inverter, warning lights and also a couple of other work truck “necessaries” on Project Bedrock — our 2011 GMC Sierra 1500 Crew Cab 4×4 – we chose it was a good concept to double-up the batteries.

Stock Chevy/GMC 1500s come with a single Group 48 battery situated in the passenger’s-side rear edge of the engine bay.

There’s additionally an unprovided battery tray on the driver’s front corner; there’s no TP2 (dual-battery option) for the 1500s, so it’s an enigma why it’s tbelow.

Wiring diagram that comes with the Cole Hereview 48530 Smart battery Isolator lines out the installation.

Whatever the factor, it does make it basic to double-up the batteries. All you require is a GM Battery Retainer (#14005061) that costs much less than $5, a second battery and a battery isolator designed to occupational via the new electronics.


The factory AC-Delco Group 48 battery is distinct to GM trucks, and it’s rated at 615 CCA (Cold Cranking Amps) through 110 RC (Reserve Capacity).

It’s practically the same to a Group 34/78 or Group 78 battery. So we decided an Odyssey 78-PC1500-A AGM battery as the auxiliary, which delivers 880 CCA and also 135 minutes RC.

The Odyssey is far more receptive to deep discharging and resistant to the tough pounding from off-pavement usage than the OEM battery.

We converted our 2011 GMC Sierra 1500 to dual batteries utilizing an Odyssey 78-PC1500-A AGM battery and also Cole Hersee Smart Battery Isolator. C/H Low Voltage Disconnect was also mounted.

To attach the 2 batteries effectively, we selected a Cole Herview Smart Battery Isolator (#48530) designed to work-related through today’s digital charging units.

The 200-amp isolator senses the voltage of both primary and also auxiliary batteries and connects/sepaprices them according to their charge, always protecting the main “cranking” battery.


For example, you pull the truck in to a jobwebsite, turn the engine off and also leave all the warning lights on.

When the isolator senses the batteries reach 12.7V it opens the solenoid relay to sepaprice the two batteries and also turns off the standing light.

This separation protects the beginning battery while permitting the auxiliary battery to proceed to power the auxiliary loads.

The finished installation is clean. Fender corner brace hregarding be rerelocated to acquire battery in and out.

When you start the truck, the charging mechanism brings the cranking battery ago to 13.2 volts (full charge), then the isolator closes, the red status light transforms on and the alternator now recharges the auxiliary battery.

Should you require a “boost” at start, an ­optional “momentary switch” deserve to be conveniently wired in to the Smart Isolator that connects both batteries for one minute once it’s activated.

We likewise installed a Cole Herview SureStart Compact Low Voltage Disconnect Switch (#48513-01) on the firewall to use as our “warm point” in between the auxiliary battery and also future strobe lights and also accessories.

This unit sounds an alarm once battery voltage drops below 12.1 volts and 60 secs later it automatically disconnects the battery (we will certainly usage it through the auxiliary) from whatever accessories are attached to it.

The switch keeps the battery protected from complete discharge once running lights or other accessories for a duration of time.

Dual batteries sets Project Bedrock up to take care of any kind of electric need we can encounter in the field. It need to occupational nicely on your Chevy or GMC as well.


If your shop doesn’t have battery cable crimping devices, consider battery terminal connectors favor those offered by uprange audio shops. DB Link ( is an excellent source.

They ­market a number of formats of battery terminals that are gold plated so they resist corrosion.

The ports in the terminal are designed to lock stripped cable ends in area via Allen set screws. No crimping crucial. Fast and also convenient.


Having a set of jumper cables that have the right to be plugged in easily is a nice item to have on a pickup. So we installed Wrangler Power Products i-Light Battery Jumper cable system.

This gives us a quick-connect plug-in point at the winch mount for jumpers in case someone else runs their battery down.

The ultra-functional cables have actually heavy-duty plugs, and also they come via a nifty LED light to present the cables are hooked up correctly at both ends.

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The kit, which has a life time warranty, is right for any kind of pickup provided in construction or landscaping. Click right here to view exactly how they are installed: Qucik-disconnect jumper cable installation.