Batteries Check Good but Truck has to be Jump Started

Hope you’re still going to replace those 4 yr old batteries.

 

Seriously, replace the other 3. The remaining 3 are going to drag that new one down and ruin it quickly.

 

First....as a shop owner....i would want to know.... If the batteries were tested hooked up to the truck still... Or unhooked...it does make a difference in Terms of the reading that a battery tester can and will give. Second as stated by another....check all grounds...hell issa good rule of thumb to clean them for corrosion. Battery bars often corrode and cause resistance inline as well...which will lead to other components working harder or not at all.

 

All pack batteries should be separated prior to testing for accuracy. Any load test through cables could give false fails. I also dont trust pack testing. For group 31 series I always clamp the tester on clean lead and not the threads. Load testing on the threads can also give false failed results. The lead adapters work but they must be clean and tight.

 

The batteries need to be fully charged to test too. It sounds as if he found the problem child. Personally I would just run three batteries before I replaced just one, in a month or so you will replace the other three, then it will not be long before you will need that one again, never ending cycle.

I have had real good luck putting old batteries even when dead, on a 2 amp charge for 24 to 48 hours to bring them back to life. An alternator will never full charge a dead battery, but a battery charger will.

 

Batteries are like apples one bad one will spoil the whole group.