Battery Voltage is Low - Anyone else?

[scram06]

I checked the voltage in both of my batterys yesterday and they both were 11.84 volts. This is after sitting for 3 days. The truck starts good and charges in the 14 volt range or 13.9 as checked with a meter. After driving the batterys both read 12.5 volts. This morning back to 11.84 volts.I was always told a battery is in the dead range under 12 volts. Anyone got any hints?I did just recently have a jake brake installed in the truck and they put a lead to the battery + side for the power to it. In that configuration power stays on to it all the time. I don't know if I had this condition prior to installing the jake.Truck runs great so I don't want to start digging around if not necessary.Thanks for any help scram06

[Mopar1973Man]

Batteries completely charged are at 12.6 Volts... Normal charging range is 13.5 to 14.5 typically.So if the batteries are slipping to under 12.0V after a few days its time to replace the batteries... Both of them at the same time!

[ccmckee]

You may want to movethe exhaust brake lead to a switched source to stop the constant drain with the key off.

[Mopar1973Man]

You may want to movethe exhaust brake lead to a switched source to stop the constant drain with the key off.

D'Oh! I missed that... Good catch...

[AH64ID]

Depending on the exhaust brake it may not use power, my Jake goes to the battery direct and my truck can sit for 8 weeks without a battery issue, it's just giving a relay the positive for switching. I would guess time for new batteries. Sears Platinum's are about the best thing out there.

[jlwelding]

I hated to do it but all they had at the auto parts were Motorcraft when I changed mine.

[AH64ID]

I hated to do it but all they had at the auto parts were Motorcraft when I changed mine.

Thats okay.. my buddy has my OEM's in his '00 F-250!

[scram06]

Turns out my trusty Craftsman meter is on the fritz. I checked the voltage with my neighbors expensive meter and got 12.55 in both batterys. I never thought my meter would give error readings. I thought it would just die one day and that would be the end of it.I was ready to start digging around on a perfectly good system! All is good, thanks for the help anyway!scram06

[Perrysburg Dodgeboy]

Crown Batteries are the only thing you will find in my vehicles. Simply the best money can buy IMO :thumbup2:Don

[Mopar1973Man]

12.55V isn't exactly a full charge either. 12.6 to 12.8 is a good full charge...Anything under 12.0 is basically dead...

[flagmanruss]

There are other parsitic drains as well. I found my batteries dead (no start) after an extended time parked. Batteries recharged fine & passed load test. I cleaned all the terminals just in case. I have a solar battery maintainer (had to repair a damaged lead) which I set on the dash & plug into the bottom 12V accessory plug (on all the time). I don't know if all electrical meters have them but all the ones I've ever owned had batteries IN THE METER.