Jump Yourself?

Boca_Shuffles

Well-known member
My GMC Duramax has two batteries. One is for the diesel and the other is for the accessories.

Since I just had the main battery replaced, could I have jump started the diesel from the accessories battery? The question is whether electrical damage to the computers would result?

This is a question for that time when you are in the middle of nowhere, with no one around, and have a dead battery.:rolleyes:
 
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jnbhobe

Well-known member
I am not positive about the chevy or dodge, But I am sure that the ford is wired in paralell. I would assume the other two are also, so jumping one to the other would do nothing. :confused::confused:
 

jimtoo

Moderator
No. You do not have an accessory battery separate from your engine battery. You basically just have 1 battery. The two batteries are hooked up in a parallel configuration. Minus to minus and positive to positive. This gives you more available power when drawing from both batteries at the same time to start the engine, as diesel engines, due to higher compression ratios take more ump from the starter to make them turn fast enough to get started.

Jim M
 

Tom of Ypsi

Well-known member
Some one will correct me if i am wrong but when replacing one battery you should replace both of them. The reason is the old battery will put a drain on the new one thus making them both equal.
 

jimtoo

Moderator
After years of GM service experience, I would recommend replacing both at the same time, if they are the same age, 2 years or more. Now if something has happened to one of the batteries, shorted cell, leak, burned strap or broken connector and it is only a year or so old, that is different. Kinda make your own call, but less than 2 years, just replace the one. But what ever you do, buy a good HD battery.

Jim M
 

boatdoc

Well-known member
Would you put one new battery in your two cell flashlight??? I didn't think so. Use the "maybe" good one for something else.
 

yondering

Retired-Full Timer
Buy a portable power suppy, basic battery in a can, keep it charged in the RV, and it will start your vehicle with ease. It can be used anywhere that 12v dc is needed. Prices run from $50.00 to $120.00 depending on where you buy. Have a Blessed day, Al W
 

porthole

Retired
My GMC Duramax has two batteries. One is for the diesel and the other is for the accessories.

Since I just had the main battery replaced, could I have jump started the diesel from the accessories battery? The question is whether electrical damage to the computers would result?

This is a question for that time when you are in the middle of nowhere, with no one around, and have a dead battery.



It was already answered but I'll add bit.

Your 2 batteries are tied together, in parallel. If you look at the right fender battery you will see "single" cables.
Look at the left fender battery and you will see "double" cables.

The GMC has a feature that turns off most electrical items after 20 minutes or so if you leave them on.
But over the last 3 years and 11 months I have had my truck I have had to jump start it for one reason or another at least 6 times.

Once it was so dead that while trying to jump it my "non resettable" engine hour meter reset to "0"

Last week my battery was dead on the coldest morning of the year so far and I figured at almost 4 years old they needed to be replaced.

You should always get a matched pair if possible. I got mine at Costco, manufacturer date of 12/09 and $69 each.
Oh, and my battery was dead this time because I left the bed light on……….

So, back to your question, if you have one dead battery - you have two.

We (local TowBoatUS) have tried the portable jump packs, but over time we have found they are usually dead when you need them, and they don't last very long anyway.

You could add a device like this to the right side fender battery and maybe save yourself some aggravation.
http://www.prioritystart.com/

My truck has battery cables that run to the rear bumper and use industrial connectors to attach jumper cables.

In a pinch, if your battery is dead and you are camping you have a couple of options.

If your truck is close enough use jumpers to connect to the trailer battery and let the trailers convertor charge it.
If not close enough pull the trailer battery and use it to jump the truck.
 

caissiel

Senior Member
I have a ground Isolation cable clamp on the main right side battery, I usally disconnect it from the truck when I boomdock, and use the driver side as an additional RV unit. When I want to recharge the batteries the truck RV battery charges much faster then the RV unit connected with 10Ga wires. So the RV batteries slowly discharges while the truck RV unit is kept loaded. Its working good so far.
 
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