2nd Gen Non-Engine/Transmission 12.6 Volts

[HEMI®Dart]

Is this correct when truck is off? Each battery shows this exactly. 5 or 6 years old. When idling it shows 14. 4 V.



I have 2 new optima redtops here.

 

[champspa]

but they're connected together , right . try separating .

 

[Road Dog]

A fully charged lead acid battery is 2. 1V per cell or 12. 6V for a 12V automotive battery. In order to charge the battery you need a slightly higher voltage so the truck voltage regulator is around 14. 4V. It'll vary with battery temperature (there's a temp sensor under one battery).

And they're connected together so they should show the same voltage.

 

[HEMI®Dart]

Unconnected they read 12. 6 v each.

 

[AEdelheit]

Is there a reason your testing them? It's possible for them to have 12. 6v sitting but drop with a load, if you have slow crank try reading the voltage while cranking. I have seen many situations where the battery reads good unloaded but drops below normal with minimal load.

 

[DavidC]

One of these are great for checking batteries. Showed a bad one in the Daughters car before she became stranded. You do not use it every day but it is sure good to have one to test batteries.
http://www.harborfreight.com/500-amp-carbon-pile-load-tester-91129.html

Dave

 

[HEMI®Dart]

Is there a reason your testing them? It's possible for them to have 12. 6v sitting but drop with a load, if you have slow crank try reading the voltage while cranking. I have seen many situations where the battery reads good unloaded but drops below normal with minimal load.

This is what I think is happening. When the truck sits at work all day in 30° ambient temps when I go to start-it I can sense a slow crank

 

[HEMI®Dart]

Lithium-Ion batteries

1200 CA 8. 8 lbs.

16 lbs (2) of battery vs. 80 (2) lbs (typical weight of a full sized CTD battery)

Would the front end rise perhaps ½" without 64 lbs?


http://www.summitracing.com/parts/lpp-c925/overview/

 

[AEdelheit]

1200 CA 8. 8 lbs.

16 lbs (2) of battery vs. 80 (2) lbs (typical weight of a full sized CTD battery)

Would the front end rise perhaps ½" without 64 lbs?


http://www.summitracing.com/parts/lpp-c925/overview/

Doubt it, I think the front spring rate is 400-500/in so I don't think there would be a measurable difference

 

[SierraRam]

1200 CA 8. 8 lbs.

16 lbs (2) of battery vs. 80 (2) lbs (typical weight of a full sized CTD battery)

Would the front end rise perhaps ½" without 64 lbs?

http://www.summitracing.com/parts/lpp-c925/overview/

$800 battery, not in my vocabulary!

 

[Road Dog]

This is what I think is happening. When the truck sits at work all day in 30° ambient temps when I go to start-it I can sense a slow crank

You need to ask a different question. Measuring the voltage doesn't tell you much about the health of the battery. You need to load test it and meassure the CCA (cold cranking amps). You can use something like that Harbor Freight tester or most battery supply places will test it for free; preferably when it's cold out. (My 11 year old batteries really slow down in the cold so it's new batteries when I start driving it again. )

 

[AEdelheit]

Hate to tell ya but Ive heard some really bad stories about newer optimas, especially in the cold

 

[kscheffler]

Optima and Odyssey batteries (AGM) should be charged to 14. 8 volts in order to get maximum life out of the battery. So what I do is put on a charger every three months that is capable of charging to 14. 8 volts. They also should have an equalize charge 2 times per year and that charge should be at 15. 5 volts. Yes I know that these are high voltages but go to the websites and read the proper charge voltages for AGM batteries. If you don't do this it will take life out of the AGM batteries. 12. 6 is on the low side for a AGM battery if it is fully charged and allow to sit for 24 hours. I consistently get 12. 9 and above on 5 year old Optima's after an equalize charge and let them sit for 24 hours. These voltages do NOT apply to normal lead acid batteries. I think the equalize voltage for lead acid is 14. 8 but don't quote me on that. I recently changed over to odyssey batteries I also heard that the new optimas are having problems. I had great luck with my 8 year old optimas.