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Called dealer about a dual battery install...

Discussion in 'Chevy Silverado Forum (GMC Sierra)' started by steved, May 4, 2013.

  1. steved

    steved Former Member

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    I installed a warn 12k winch a while back, add to the fact I've always wanted the dual batteries; decided to call about it. The dealer I bought the truck from is getting me a price. I figured if I have them install it, then its on them if it screws something up.

    I fully expect to have sticker shock...
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  2. donl

    donl New Member

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    Since the Duramax that came in your pickup as an option has 2 batteries it might not be too big a hassle. If (a mighty big word) the gas engine doesn't have something sitting where the second battery would be in the Duramax. Seems like anytime you are going through a dealer you can expect some sticker shock. I wouldn't be surprised if there isn't someone who has been through this already. Good luck.
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  3. thrasher

    thrasher New Member

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    I may be mistaken, but I think you can buy a dual battery kit at Auto Zone & the like for around $60.00 plus the cost of the second battery. i believe the only other mod would be a higher output alternator, again available @ Auto Zone or Ebay/Amazon etc...
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  4. steved

    steved Former Member

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    These 2012s have the second battery tray (like previous years) and what not...I believe there is a build code for dual batteries in the 6.0L also (probably another option for the snow plow package?), its a matter of whether you opted for it.

    The reason to do a factory install is to avoid any questions about the install down the road. The 2012 has a 160A alternator, so that's not a concern.
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  5. SurrealOne

    SurrealOne Former Member

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    Questions from whom? About what? Why do you care if someone asks questions about the installation of dual batteries in your truck?
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  6. steved

    steved Former Member

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    If the dealer installs it and it burns something up...its on them, not me. For something like this, a few bucks in savings isn't worth the risk of the warranty.
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  7. SurrealOne

    SurrealOne Former Member

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    The liklihood of burning something up is extremely low if you know what you're doing. And by extremely low -- I mean it would only happen out of carelessness.

    Frankly, I'd never let the dealer do a dual battery setup for me. I don't like the cable GM uses for its positive and ground connections to the batteries. The strand count is too low, it's highly inflexible, and it's usually 8ga where I prefer 1/0AWG. My winch can demand 300amps very quickly if something gets stuck while winching ... and I want upsized cables to handle it ... as well as 300amp ANL fuses in place in case the load causes even more demand.

    The chance of such a draw is very low, as I'm pretty conservative/cautious when winching ... but I build for the worst case scenario so that I can have absolute confidence in my setup. (I even upsized my Warn winch's +12v and common ground cables. :) )
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  8. Conlan Rose

    Conlan Rose Super Moderator

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    GM factory wire blows. 8 gauge wire is usually rated around 55-80 amps so half what it needs to be for a truck alt. I recently upgraded my alt and fuse box cables to 1/0 awg and 4 awg respectively. Now the truck's electrical system runs much better and can easily handle extra draw.

    Ok now on point, you should upgrade your cables it's worth the money. Also [MENTION=50075]SurrealOne[/MENTION] has an amazing set up so I'd listen to his advice. You may be able to ask the dealer to install better cables that your choose so they know they are there and can't yell at you for warranty issues.
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  9. steved

    steved Former Member

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    Well, the dealer "pieced" a dual battery setup together; complete with a battery tray...which immediately made me wonder if they ever did this before. Basically they were going to install the pieces for a diesel to get the dual batteries. Total cost, north of $1,100.

    For that price, it was a no-brainer to DIY. I call the local Deka (East Penn Manufacturing) and talked to them. They not only sell their batteries, they custom make cables. I stopped today, bought an OE-style 648 battery (680 CCA) and two custom length 1ga cables with clamps on one end and eyelets on the other. They also had the OE-style battery hold-down. Total cost with battery (a first grade, not a factory second) was $188. It could have been $125 if I had used a factory second. Brought the stuff home, and really didn't plan to install it tonight; but took about 30 minutes to install. Pictures:

    [​IMG]

    [​IMG]

    [​IMG]
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  10. shibby2oo8

    shibby2oo8 New Member

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    Summit has a kit where you can switch between the batteries so you can isolate either one or self jump start. Nothing wrong with that setup but i would like to disconnect the reserve to prolong the batt life and ease up on the alt when charging both with the other truck acc's ontop.
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  11. SurrealOne

    SurrealOne Former Member

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    There ya go, [MENTION=54243]steved[/MENTION]. Your application doesn't call for an isolator, I take it?
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  12. steved

    steved Former Member

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    My application doesn't need an isolator, the truck will be running whenever the winch would be running. I don't sit with the ignition off for very long anyway.
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  13. GATUC

    GATUC New Member

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    I'm "confused". I have a 2012 Silverado, 1500, 5.3L gas. Putting a 12,000LB winch on it with 6.6HP motor. I have the factory "empty" battery tray. I feel I "should" put a second battery on it. Many places say put an isolator on it, many places say no need???? I feel like steved here, don't need an isolator, but then some places state it may over work your alternator not doing so??? What's a person to do??? I do not have a clue???? Please help....
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  14. Pikey

    Pikey Moderator

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    I don't think that it would "overwork" the alt. Basically the alternator is just going to keep both batteries charged. If you are not killing the battery now with one battery (because the alt can not keep it charged) then I highly doubt that there would be any damage from 2 batteries. Actually, I would think that it would prolong your alt life, as when you need more power there is another source and the alternator does not need to run at max production to keep up with your needs. Sure, if somehow you killed both batteries and attempted to use the alternator to charge them both at the same time, then you may have an issue. But, even with one battery it is never a good idea to recharge a dead battery with your alternator. An alternator is meant to maintain your battery charge, not recharge a dead battery. I believe that an isolator is always a good idea. I just like the fact the you can tailgate/ party with the radio on (or multiple things charging) and the truck off for hours, you run off of one battery. Lets say that that battery completely dies. You always have the other battery at full charge to restart the truck and get you home. You get home, recharge the dead battery and all is good. This is just my opinion, I am sure others will chime in.
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  15. j cat

    j cat Active Member

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    if the battery is discharged the alternator can only pump into the battery about 15 amps when the temp is about 70degf...with 2 batteries dead the alternator will need to produce 30 amps for the batteries. then you add on about 60 amps for the other stuff... so that comes to 90 amps. that would be the worst case ...

    2 batteries actually reduce alternator power surges from these motor winches or more commonly from high power sound generators ...they act as a capacitor to reduce current power surges that can damage the alternator .
    #15
  16. WorthFlorida

    WorthFlorida New Member

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    Better check this out http://en.wikipedia.org/wiki/Battery_isolator

    I have the same truck and the second tray does look inviting to use it. The biggest problem you can have is if one of the batteries dies. In the heat of Florida, most batteries have a instant death because one cell shorts out. Up north it's usually a slow death in cold weather. Should one battery have a short it is now below 10 volts and the starter motor will never spin. With a second battery in parallel the voltage difference will drain the good battery and the current flow will reverse. Depending how the battery died it can draw a lot of current from the good battery. The cables between them will get warm and maybe hot enough to melt the insulation. An isolator sure makes sense because it can cost you dollars later on. You might stop by a Chevy/GMC dealer and see if there are any duramax trucks around and look at the battery setup. I kind of doubt both batteries are in parallel. Maybe ask a dealer mechanic who is trained on duramax engines.
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  17. j cat

    j cat Active Member

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    batteries fail in many ways. cells shorting out will occur in any climate. normally these failures show up when the extreme heat/cold arrive. this is when the cell short shows itself. the other common failure is when a battery will internally open due to defective design or not being properly secured/handled. this is where the battery output will show a good reading of 12.5 volts , but when a load is placed on it the volts drops out.

    with the newer trucks the battery mounted on the fire wall is not what I recommend. this is an area of excessive heat. in a hot climate I would move this to the front of the vehicle.

    I usually get 7 years out of my vehicle batteries. I keep them clean and insure they are covered on top with a rubber shield to protect from corrosives ...

    The isolator diodes are a great upgrade with 2 batteries but , as long as both batteries are matched and of the same age this should not be required . you must use large guage wire than OEM with 2 batteries. I would also install a fuse between them and cover the cables with a proetctive loom material.
    #17
  18. WorthFlorida

    WorthFlorida New Member

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    I'm living 23 years in South Florida and have replaced many batteries including my two son's vehicles. From when I got my first car in 1971 I lived in Upstate NY and Illinois, very cold winters. I learned that if the car battery is 5 years old, good or bad, I would replaced them. Not starting once or twice when it was 0 degrees in the morning was no fun or the wife would call you while you're at work that the car won't and has the kids. AAA or not always a hassle. For the most part I rarely had a battery die prematurely. Florida heat is another story, On average it seems like it's three years and your doomed. I once had a battery die while I was moving it off a set of ramps to change the oil. Just bam, its dead and a hard short it is still difficult to jump start. I did have one go about 4 years, an OEM on a Highlander and it was a slow death so before the wife was stuck i changed it out. I've bought cheap and high price batteries and there seems to be no difference in the heat. I liked Autozone batteries because you can go to any store, they'll find your sales record when the battery was purchased and easily pro rate it. IF you buy a six year warranty battery, it almost guaranteed that you get a new battery with a prorated adjustment. This did happened on the replacement one for the Highlander.

    One year ago I got my new truck, picked it up on Monday and by Thursday the battery went bad. The dealer did
    replaced it. My luck it was one of the millions of good batteries that GM buys and mine the bad out of the box.
    #18
  19. j cat

    j cat Active Member

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    very surprised with your battery failure rate. I get 6-7 years out of the oem new vehicle battery AC DELCO...then I got some walmart batteries with 900CCA and thats what I got now in the 2000 silverado. this is the only replacement purchased so far, looks like I am due to replace this as , it is going on the 7th year now.

    back in the ancient history of my life I only got 3-4 years out of my batteries. 3 starter motors in 110,000 miles. this was a 1967 olds. that vehicle took just too much cranking from day one [NEW] on a cold start . after that vehicle , I have had no starter of battery problems with short life failures....

    I do not recommend the sears die hard batteries. they internally open ... so that means suddenly you get nothing . over priced also.

    my 1983 17 years 3 batteries total I purchased 2 . had to replace the starter at 15 years. 380,000 miles when sold .
    #19

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