Aux Battery

dcovell · September 19, 2007

I have a spare brand new battery and want to put it in the aux battery spot on my Sierra 1500 NBS. My question is, is there a "kit" from GM for the battery cables as it is a factory option on the diesels I thought they might have a wiring kit. Otherwise I can just get some 0 or 2 guage braided cabling and wire it up in parallel.

mljenkins · September 20, 2007

I am curious where the aux battery spot is. I thought only the 3/4 and 1 tons had a place for an aux battery. I was wanting to wire in a second battery to feed my trailer when I was camping, aside from running a power inverter for extended periods.

Matt

Zembonez · September 20, 2007

I am curious where the aux battery spot is. I thought only the 3/4 and 1 tons had a place for an aux battery. I was wanting to wire in a second battery to feed my trailer when I was camping, aside from running a power inverter for extended periods.

Matt

Mine has an extra "battery tray" behind the left headlight. I assume all GMT900s are the same? Is that where the diesels have a second battery?

mljenkins · September 20, 2007

Mine has an extra "battery tray" behind the left headlight. I assume all GMT900s are the same? Is that where the diesels have a second battery?

I have an '06 Silverado, so maybe that's something new in the 1/2 ton '07s. I was looking for a place to mount an aux battery about 6 months ago and gave up. Drat...

Matt

Paul58 · September 20, 2007

I have the GMT900 and it's got the spare battery shelf as well. I'd like to add a second battery, it would help when towing our TT.

asilverblazer · September 20, 2007

Ditto that.

MS3DALE · September 20, 2007

Mine has an extra "battery tray" behind the left headlight. I assume all GMT900s are the same? Is that where the diesels have a second battery?

I have an '06 Silverado, so maybe that's something new in the 1/2 ton '07s. I was looking for a place to mount an aux battery about 6 months ago and gave up. Drat...

Matt

Matt,The auxilary battery on your truck (GMT800 trucks) goes on the RH side,Right in front of the firewall,Underneath the fender brace.

dcovell · September 20, 2007

So anyone know of any part numbers or a good way to hook up the aux battery?

mljenkins · September 20, 2007

So anyone know of any part numbers or a good way to hook up the aux battery?

You could wire it in parallel, but you won't have the electronics to disconnect it from the main battery to prevent draining it. I found one company on the net doing a Google search that has the tray and electronics. I would hope they would make something more automated. I would hate to have to switch it manually.

http://www.wranglernw.com/ProductPickerRes...amp;itemtype=11

Matt

dcovell · September 20, 2007

I have a 2007 with the new body style and it already has a tray. Just needs wiring. Now why would I want to switch it on and off, basically in parallel it would just be an extension to the existing battery. I just want to have it look stock and be a good quality cable.

dcovell · September 20, 2007

Now I do understand that if one of the batteries is failing it can drain the other battery but with two brand new ones would that be an issue? Do they have to be the same size battery?

mljenkins · September 21, 2007

Now I do understand that if one of the batteries is failing it can drain the other battery but with two brand new ones would that be an issue? Do they have to be the same size battery?

As long as they were both 12V batteries (would have to be to wire in parallel) I would think they would not drain each other. But I'm no electrical engineer by no means :-)

They usually have a relay to keep the primary battery from being drained down by accessories, such as a travel trailer or using power outlets inside the vehicle.

Here's some more info:

http://www.smithae.com/surepower.html

Zembonez · September 21, 2007

Now I do understand that if one of the batteries is failing it can drain the other battery but with two brand new ones would that be an issue? Do they have to be the same size battery?

Size of the battery is not an issue. Obviously they both have to be 12 volt. Wired in parallel they would function as one super battery. For cables, many speed shops are able to make up cables of any length. They also have NHRA rated disconnects or switches as required on certified drag cars. Jegs or Summit Racing should be a good sources also. I've probably spent 20,000 dollars with them over the years. Their prices are good and they ship quickly.

It might take a little engineering to make it look stock but that is what makes this fun. Here are some links.

http://www.jegs.com

http://www.summitracing.com

Cheers!

mattro · September 21, 2007

Gmpartsdirect.com will give you the part number and I believe its only $14 or $25 for the tray itself I was gonna go that way with my truck....just e-mail them what u want and ur vin number and they can get anything for you

nccrew · September 21, 2007

Wow - they are pretty proud of that setup - $543.73 - ouch

So anyone know of any part numbers or a good way to hook up the aux battery?

You could wire it in parallel, but you won't have the electronics to disconnect it from the main battery to prevent draining it. I found one company on the net doing a Google search that has the tray and electronics. I would hope they would make something more automated. I would hate to have to switch it manually.

http://www.wranglernw.com/ProductPickerRes...amp;itemtype=11

Matt