Normal operating battery voltage

[RamGuy84]

For those of you with a Cummins, what is your normal operating battery voltage....idling and cruise?

I feel like my 2019 was usually 14-14.2V.

I noticed today my new 2020 it was 13.9V and now it’s down to 13.6V. Cause for concern or no?

 

[Hawk375]

my 2019 is usually 13.6 - 13.8

 

[BobbyT]

The computer will tell the alternator to put out what it needs depending on the battery levels and electrical loads. anything from 13-14 volts is fine. If you get below 13 volts after its been running for a while, then you should investigate.

 

[Rich]

While running on trips, mine fluctuates between 13.7 - 14.1

 

[Zeroday]

I keep the battery level in one of the corner spots, so I don't know actual voltage but I can say it regularly stays just under the halfway mark. I'm assuming that's 14V? I'll bring up the actual voltage next time I drive it.

 

[elephantrider]

13.7 is what mine usually runs.

 

[carlrx7]

Voltage will depend on load, state of charge, and temperature. Hot, 13.2 - 13.6v. cold 14.0-14.4v is my observations (dual 220A alts)

 

[Ironhead1970]

I just bought a used 2022 2500 diesel with 30, 000 miles from the dealership Took it for a shake down cruise for a few hundred miles and the voltage dropped to 11.2 went to a parts store where it showed the alternator was bad. Spent the night in a hotel didn't want break down somewhere. In the morning it started right up voltage was 13.8 went to the same parts store they retested with the same machine used the night before and found no problems with the charging system. I'm thinking there's a short somewhere. There's a few other problems like it keeps losing enough coolant to turn on the idiot light but it runs at 195 degrees F in 100 degree summer in Texas.

 

[Rockcrawlindude]

I just bought a used 2022 2500 diesel with 30, 000 miles from the dealership Took it for a shake down cruise for a few hundred miles and the voltage dropped to 11.2 went to a parts store where it showed the alternator was bad. Spent the night in a hotel didn't want break down somewhere. In the morning it started right up voltage was 13.8 went to the same parts store they retested with the same machine used the night before and found no problems with the charging system. I'm thinking there's a short somewhere. There's a few other problems like it keeps losing enough coolant to turn on the idiot light but it runs at 195 degrees F in 100 degree summer in Texas.

Factory battery? If so they’re junk

 

[Ironhead1970]

Voltage will depend on load, state of charge, and temperature. Hot, 13.2 - 13.6v. cold 14.0-14.4v is my observations (dual 220A alts)

The voltage at the start of my drive on Sunday was 13.8 and dropped to 11.4. Next day on Monday it was back up to 13.8 the whole day. Then on Tuesday on the way to the service department at the dealership voltage was 11.2. I'm hoping they fixed it with a new alternator. The truck only has 27,000 miles on it the diesel engine is not broken in yet and still under factory 5 year 100,000 mile warranty.
Thank you for your reply
2022 2500 diesel 4x4 Laramie

 

[MinRAM2500]

The computer will tell the alternator to put out what it needs depending on the battery levels and electrical loads. anything from 13-14 volts is fine. If you get below 13 volts after its been running for a while, then you should investigate.

2024 Ram 2500 6.7, 73K miles
New to me 7 months ago first time just now - she didn't start
nothing but perfect performance up until now
sounded like the starter was engaging but didn't have strength to turn
Tried several times got a jump from a friend started right up first try
I believe I've heard a tiny squeal coming from my alternator two or three times when first starting in the morning - no guarantee that's what it is
but the last time I took time and focus to narrow it down and it did seem to come from the alternator.
I'm going to put a gauge on the batteries and the alternator and see what I've got
I just put this out there to somebody that sounds very knowledgeable about these vehicles in specific to see if there's anything else I need to watch for
Thank you in advance
Sam

 

[MinRAM2500]

The computer will tell the alternator to put out what it needs depending on the battery levels and electrical loads. anything from 13-14 volts is fine. If you get below 13 volts after its been running for a while, then you should investigate.

Also this just happened & I'm driving up the road 45 mph, 1,000 rpm + or - (just left the job) voltage meter on dash reading steady at 14.0 - 14.1