Group 31 battery upgrade

[CalifExplorer]

Hi all
Seemed like a good idea to upgrade battery size since I'm also installing a few more accessories.
After installing the setup shown in the photo (including cleaning up terminal plate connections of paint) the battery couldn't turn over the truck. A quick jumper cable connection fired things right up. A ten-mile drive and some idling was not enough to sufficiently charge battery to turn over starter at normal speed/strength, so I connected a battery charger at 8 amp for a couple hours...still not great battery performance.
I really figured a deep-cycle group 31-size battery would be enough to start a cruise ship....I'm unsure what's going on.
Battery purchased via Amazon. I have no idea how long it may have been on a shelf.
Anyone have experience with this?

 

[New Holland Overland]

Hi all
Seemed like a good idea to upgrade battery size since I'm also installing a few more accessories.
After installing the setup shown in the photo (including cleaning up terminal plate connections of paint) the battery couldn't turn over the truck. A quick jumper cable connection fired things right up. A ten-mile drive and some idling was not enough to sufficiently charge battery to turn over starter at normal speed/strength, so I connected a battery charger at 8 amp for a couple hours...still not great battery performance.
I really figured a deep-cycle group 31-size battery would be enough to start a cruise ship....I'm unsure what's going on.
Battery purchased via Amazon. I have no idea how long it may have been on a shelf.
Anyone have experience with this?

Have you checked the sitting voltage of the battery?

 

[CalifExplorer]

Have you checked the sitting voltage of the battery?

I should get a voltmeter and do that

 

[New Holland Overland]

I should get a voltmeter and do that

Also check the manufactures date:

How to Tell How Old a Car Battery Is

A car battery's lifespan escapes a car owner's consideration until the battery fails and renders the vehicle immobile. Often, this occurs at the most inopportune time and requires a call to roadside assistance and a tow to a service garage.

www.jdpower.com