Finally stranded me...

[Tonyv__]

Nope, not like a dying battery. This was the strangest "reluctant" start I've ever witnessed. It literally clicked, turned over EXACTLY ONCE, stopped for about 2-3 seconds flat, then started up normally.

Like this. Minus the alarm?

 

[jyi786]

Like this. Minus the alarm?

Whoa, that's it! I never thought someone would actually catch it on video!

 

[Tonyv__]

Whoa, that's it! I never thought someone would actually catch it on video!

Now I have to figure out if the battery is a dud (2 months old) or if my starter is in its way out. The battery is doing some funky stuff via the multimeter and when I replaced the battery the problem went away until the other day. However I still felt like it was a slower crank even with the new battery. Never seemed perfect to me…

Do you know if the dealer was able to actually test your starter or did they just change it out

 

[jyi786]

Now I have to figure out if the battery is a dud (2 months old) or if my starter is in its way out. The battery is doing some funky stuff via the multimeter and when I replaced the battery the problem went away until the other day. However I still felt like it was a slower crank even with the new battery. Never seemed perfect to me…

Do you know if the dealer was able to actually test your starter or did they just change it out

They didn't have time to test it. They simply diagnosed it was bad (as well as one of my batteries) and changed it out.

 

[bboyce10]

I added the second battery myself. They are simply wired up in parallel using the stock GM battery kit, so basically acts like one battery.

I learned via research last night that I should be rotating (swapping) the batteries, side to side, every 6-9 months. It totally makes sense, since all the accessories are on the main battery. My guess is that I wore down the main battery; this is now the second time I've done so. Rotating the batteries will help level out wear, from what I read.

When batteries are wired in parallel, you are correct that it acts like one 12V battery. The second battery will add additional amps. There is no benefit to swapping,as accessories will draw off both batteries equally (since electrically they are acting as one).

 

[TollKeeper]

When batteries are wired in parallel, you are correct that it acts like one 12V battery. The second battery will add additional amps. There is no benefit to swapping,as accessories will draw off both batteries equally (since electrically they are acting as one).

Technically true, however, electricity still follows the path of least resistance, hence why wire gauge is really important when wiring in a second battery, alternators, and amps.

 

[Tonyv__]

New starter fixed her up. Haven’t heard it turn over this fast in quite a while. Bummed I threw away $200 on a battery but it is what it is. Never had a starter slow down on me. Just usually flat out dies or you give it the good old tap with a hammer then try again and it kicks over.

 

[BG1988]

I added the second battery myself. They are simply wired up in parallel using the stock GM battery kit, so basically acts like one battery.

I learned via research last night that I should be rotating (swapping) the batteries, side to side, every 6-9 months. It totally makes sense, since all the accessories are on the main battery. My guess is that I wore down the main battery; this is now the second time I've done so. Rotating the batteries will help level out wear, from what I read.

smoothing capacitor will start it even faster... this can supply the amperage faster then a lead acid battery

New starter fixed her up. Haven’t heard it turn over this fast in quite a while. Bummed I threw away $200 on a battery but it is what it is. Never had a starter slow down on me. Just usually flat out dies or you give it the good old tap with a hammer then try again and it kicks over.

Fastest Tahoe start in a 1/10th of second

looks like it took longer for the computer to communicate more then anything

 

[RED TAHOE LS]

I'm sure Delco batteries are good enough. Personally, I buy construction, not brand. AGM for me.

And personally, I would have gone through the entire charging system - checking batteries and alternator, before replacing the starter. Not sure I buy the whole 150k starter dying thing. I currently own 7 vehicles, have owned a bunch in my lifetime, and can't remember the last time I replaced a starter. My two GMT900 trucks have 215k and 135k miles with original starters.

If the batteries are simply wired in parallel, I can't possibly see how "rotating" them could make any difference. Assuming you've used proper-gauge wires, any electrical load should be spread evenly between the two. Ditto charging current from the alternator.

I've had dual batteries in my Suburban since 2014, and dual batteries in my Denali since 2016. I don't rotate them and I've only replaced two out of the four in that time.

Also, as you've found out, if you don't use an isolator, there's really no benefit to dual batteries, it's no different than just having a larger single battery. If the truck doesn't start, you still need a jump. One time my Denali died, the primary was so dead it wouldn't even engage the isolator. People watched me get out my cables and jump-start myself. Jaws dropped at my sorcery. LoL

Most of the time the battery is just too far gone, my hoe came with 800 CCA battery and i think I'm on my third one @227k, original starter, two alternators. Delco freedom is hard to beat.

 

[jyi786]

smoothing capacitor will start it even faster... this can supply the amperage faster then a lead acid battery

I'd like to know more about this. Where can I find info and how to install? Google search didn't bring up anything relevant.