Battery and starting

[Garrett2500]

My truck can sit over night and depending on temperature it will not start. Started it the night before. But would not start the next afternoon at 12. Temperatures overnight were 50 degrees. Put batteries on proper charger days prior and no error sighs. What am I doing wrong? This is my wife's daily driver. Thank you. 2006 3500 optima batties

 

[seafish]

A"proper charger" with "no error signs" may or may NOT mean anything.
A battery can be fully charged and still not able to carry enough current do to internal degradation.

Since they're Optima and sealed, there is no way to use a Battery hygrometer on them, so youll need to get them load tested at a reputable parts store. Load testing will tell you whats up with their internal state and if they can still carry a decent load.

That being said, you'd best ALSO start with the 12v basics --

Inspect, clean and tighten ALL battery terminals including all ground connections.
You are looking for corrosion, dirt and ANY signs of looseness and cable failure.

If BOTH the batteries and connections check out good, then problem is with the starter or its connections.

 

[petersonj]

My truck can sit over night and depending on temperature it will not start. Started it the night before. But would not start the next afternoon at 12.

Need more detail on "will not start". Does this mean that the starter cranks the engine, but the engine doesn't start? or does it mean the starter does not operate?

Also, other information will be helpful - truck year, model, transmission type, miles on truck, previous problems or previous work done, etc.

- John

 

[Signal73]

More helpful info would be, How OLD are the batteries?

 

[AH64ID]

What is the battery voltage 4 hours after you shut down or stop charging them?

 

[Topzide]

Age will dictate what needs to be done. If over 5+ years without being on a tender during periods of inactivity, time for them to be replaced. Showing 12.5 volts after charging means nothing at all. That's just surface charge, what shows after charging and then sitting for 24 hours before installing? That would give some answers. Load testing is the only true way to know what condition that they're in. More info as @petersonj and @Signal73 has mentioned.