RAM truck is a battery eater

[CoastyAV8R]

My batteries are the original batteries (2019 2500), I keep it on a trickle charger in my shop because I don't drive it a lot (almost 36,000 miles) and I live in a mild climate in Oregon. Probably just jinx'ed myself with that but the truck is pampered and sometimes it's just the luck of the draw. My 2016 I had for 4.5 years still had the original batteries in it as well when I sold that one.

 

[JR]

I'm still on one original Mopar batt from 2014.
Yes I know....not supposed to mix and match. But the driver side tanked out fairly early on and I just so happened to have a newer group 31 that (barely) fit, and they've coexisted just fine. Winter time they see a maintainer fairly frequently, and I don't go far in the winter, but they'll both be getting replaced in the spring. The 31 may find a new home in my tractor. That battery is a few years older.

 

[Grumpy8811]

I'm still on one original Mopar batt from 2014.
Yes I know....not supposed to mix and match. But the driver side tanked out fairly early on and I just so happened to have a newer group 31 that (barely) fit, and they've coexisted just fine. Winter time they see a maintainer fairly frequently, and I don't go far in the winter, but they'll both be getting replaced in the spring. The 31 may find a new home in my tractor. That battery is a few years older.

whether to mix or or match batteries is more of an internet story than the real 100% deal.

replacing both batteries at the same time more of a good practices idea than an absolute that is written on a stone tablet.

For instance truck has 5 year old batteries and one of them fails, best practice would be to replace both
but if the batteries were 3 months old and one of the batteries failed for whatever reason, nothing would be wrong with only replacing one of them.

Problem lies in the gray area where you have one new battery and one that is a couple years old
then you end up replacing one battery at a time over and over.. which gets tiring.

 

[JR]

Agreed. Passenger side load tested the same as the nearly new 31 so I ran with it. And, it's load tested fine every year since but am seeing a slow decline and know that I am past being on borrowed time at this point.

 

[crispyboy]

I should buy a lottery ticket. My truck batteries are 7 years old here in December 2024. I can tell they are getting up in age. I do allow the grid heater to cycle and the truck starts quicker (less revolutions) than if I bypass the grid heater cycle.
My local battery guy told me to always keep a "dumb charger" around so I could always use it to get a battery going and then swap it to the "smart charger".
I bought a Noco GB150 boost last year to carry in the truck. I would rather use a jump box than hook my truck up to someone else's vehicle with a questionable electrical system. I used the Noco at a campground to jump start a guy with an old Ford 7.3 diesel engine. He had recently installed a new alternator before this trip. As typical big box auto parts the new alternator didn't make it through the his first trip. The Noco struggled and took several attempts before the truck finally fired up. It did work though.
On a recent trip to see my in-laws I found an unused tool box in his garage. Apparently the tool was long gone so I repurposed the box for the Noco charger. The original Noco cardboard box was starting to get torn up.

 

[AH64ID]

I can tell they are getting up in age. I do allow the grid heater to cycle and the truck starts quicker (less revolutions) than if I bypass the grid heater cycle.

I’d like to see a decent test on this. I can’t say I’ve ever noticed a difference above 0°F for starting with or without the grid heater on all 3 of the Cummins trucks I’ve owned.

 

[Diesel85]

I should buy a lottery ticket. My truck batteries are 7 years old here in December 2024. I can tell they are getting up in age. I do allow the grid heater to cycle and the truck starts quicker (less revolutions) than if I bypass the grid heater cycle.
My local battery guy told me to always keep a "dumb charger" around so I could always use it to get a battery going and then swap it to the "smart charger".
I bought a Noco GB150 boost last year to carry in the truck. I would rather use a jump box than hook my truck up to someone else's vehicle with a questionable electrical system. I used the Noco at a campground to jump start a guy with an old Ford 7.3 diesel engine. He had recently installed a new alternator before this trip. As typical big box auto parts the new alternator didn't make it through the his first trip. The Noco struggled and took several attempts before the truck finally fired up. It did work though.
On a recent trip to see my in-laws I found an unused tool box in his garage. Apparently the tool was long gone so I repurposed the box for the Noco charger. The original Noco cardboard box was starting to get torn up.
View attachment 142643 View attachment 142644

I use my leftover DeWalt boxes for stuff like that! We think alike!

 

[Tuesdak]

whether to mix or or match batteries is more of an internet story than the real 100% deal.

At least one OEM, Optima Batteries, recommends in writing to replace them in pairs.

https://www.optimabatteries.com/experience/blog/why-do-diesel-trucks-have-two-batteries

 

[DavidComeau]

2017 leftover bought in fall of 18 @ Kernersville NC.
I checked batteries at the dealership right before I drove it home, they had been replaced with dated 18 before delivery.
Finally had to buy a new pair Nov 24. I'm satisfied....sorry did not look at brand
ABS constant problem....
now @ 47k needs tires.

 

[Grumpy8811]

At least one OEM, Optima Batteries, recommends in writing to replace them in pairs.

https://www.optimabatteries.com/experience/blog/why-do-diesel-trucks-have-two-batteries

I'm sure they do... but its always a good idea to treat " advice" from entities with a vested financial interest in the sale of product
with a bit of skepticism as they profit from the sale of batteries as well as applying some common sense to the situation.

 

[Signal73]

2017 leftover bought in fall of 18 @ Kernersville NC.
I checked batteries at the dealership right before I drove it home, they had been replaced with dated 18 before delivery.
Finally had to buy a new pair Nov 24. I'm satisfied....sorry did not look at brand
ABS constant problem....
now @ 47k needs tires.

Just in case you didn’t hear about the abs recall

https://www.consumerreports.org/car...-risk-antilock-brake-abs-failure-a8228469455/

 

[Jim W]

whether to mix or or match batteries is more of an internet story than the real 100% deal.

replacing both batteries at the same time more of a good practices idea than an absolute that is written on a stone tablet.

For instance truck has 5 year old batteries and one of them fails, best practice would be to replace both
but if the batteries were 3 months old and one of the batteries failed for whatever reason, nothing would be wrong with only replacing one of them.

Problem lies in the gray area where you have one new battery and one that is a couple years old
then you end up replacing one battery at a time over and over.. which gets tiring.

I disagree with your conclusion based on real world experience which I have seen in over 40 years of designing heavy equipment and owning HD trucks with two battery systems. This is just my opinion so, take it for what it is worth.

When one battery is replaced for whatever reason in a two or more-battery system the alternator does not know which battery is old and the other one is new. So, the alternator ends up over charging one of the batteries (usually new) as it is trying to provide the correct voltage to both batteries. I have seen tractors that have had the batteries explode due to the alternator trying to charge a fully charge battery, since the older battery is in need of charging.

When in doubt replace both batteries just to be safe. As I mention in my one post, I did this with a set of batteries that were only 7-months old. One of the batteries failed due to a defective negative post. I replace both, one under warranty and the other I purchased.

 

[Grumpy8811]

I disagree with your conclusion based on real world experience which I have seen in over 40 years of designing heavy equipment and owning HD trucks with two battery systems. This is just my opinion so, take it for what it is worth.

When one battery is replaced for whatever reason in a two or more-battery system the alternator does not know which battery is old and the other one is new. So, the alternator ends up over charging one of the batteries (usually new) as it is trying to provide the correct voltage to both batteries. I have seen tractors that have had the batteries explode due to the alternator trying to charge a fully charge battery, since the older battery is in need of charging.

When in doubt replace both batteries just to be safe. As I mention in my one post, I did this with a set of batteries that were only 7-months old. One of the batteries failed due to a defective negative post. I replace both, one under warranty and the other I purchased.

they do make a device called a carbon pile... and that will tell you more about a battery than anything else in the world.. look at it this way, if you have a 700CCA battery and it passes a load test, it is still good.. so why just change a battery because? if they were 5 years old, yeah, change them both, but that 7 month thing is early on in the gray area.. batteries suffer from 2 things, generally a cell fails or a loss of capacity, which occurs naturally over a batteries life time... but if you load tested a slightly used 800 CCA battery and it passed with flying colors, why throw 200 dollars away..

. Not every one wants to throw away a 200 dollar battery just because the internet said to do it
Lets face facts too, some people are for more afraid of mechanical failures due to their own insecurities than other.

Anyway you look at it the alternator in a vehicle only knows what the voltage regulation system commands it to do..
it doesn't know a thing about what one individual batter's condition is.
The VR only senses voltage at one given point in the vehicle electrical system..
So the main difference is where the regulator measures voltage.
there are two general methods voltage is measured in a DC automotive system...
the voltage regulator may measure voltage directly in the B+ system somewhere in the 12V system other than the alternator
whereas a different system may only regulate output voltage based on what the alternator output B+ is.


one method of VR sacrifices the batteries to save the alternator
the other method sacrifices the alternator to save the batteries

either way only VR sees one particular point in the electrical system and responds that that input to regulate field strength to control system voltage...
throw in the battery temp sensor on Mopar to add an extra degree of nonsense but the fact of the matter is VR is still only regulated based on one known point in the vehicle electrical system

 

[Diesel85]

I disagree with your conclusion based on real world experience which I have seen in over 40 years of designing heavy equipment and owning HD trucks with two battery systems. This is just my opinion so, take it for what it is worth.

When one battery is replaced for whatever reason in a two or more-battery system the alternator does not know which battery is old and the other one is new. So, the alternator ends up over charging one of the batteries (usually new) as it is trying to provide the correct voltage to both batteries. I have seen tractors that have had the batteries explode due to the alternator trying to charge a fully charge battery, since the older battery is in need of charging.

When in doubt replace both batteries just to be safe. As I mention in my one post, I did this with a set of batteries that were only 7-months old. One of the batteries failed due to a defective negative post. I replace both, one under warranty and the other I purchased.

I've helped maintain large scale UPS (battery backup) systems, and generally speaking, if you want to replace one battery (we call them jars), and you need to do OHMIC testing of all jars before replacing the battery. If any fall outside of the new battery, they need to replaced as well. Basically adjacent jars is what they are called. Is it fool proof? Nope. I've seen some pretty rad stuff doing that job if things aren't balanced just right.

If it's just a few batteries, we used to tell the customer to replace them all in a smaller array to avoid bad things from happening.

Batteries are interesting pieces of technology to say the least. One day they could test out fine, we go to replace a single battery in a string, and next day the customer calls wondering why two batteries decided to degas (that lovely sulfur and burnt plastic smell) over night.

 

[Grumpy8811]

I've helped maintain large scale UPS (battery backup) systems, and generally speaking, if you want to replace one battery (we call them jars), and you need to do OHMIC testing of all jars before replacing the battery. If any fall outside of the new battery, they need to replaced as well. Basically adjacent jars is what they are called. Is it fool proof? Nope. I've seen some pretty rad stuff doing that job if things aren't balanced just right.

If it's just a few batteries, we used to tell the customer to replace them all in a smaller array to avoid bad things from happening.

Batteries are interesting pieces of technology to say the least. One day they could test out fine, we go to replace a single battery in a string, and next day the customer calls wondering why two batteries decided to degas (that lovely sulfur and burnt plastic smell) over night.

lets face it, you can check everything electrical right now and its fine and tomorrow the DOT flagged you because a light is out..
you know what they say: you know when something electrical is bad because the genie let the smoke out..


its much easier for the common man to just change both.. and its always easier for the vendor to recommend replacing items than it is to recommend the customer spend labor time on testing, recharging etc.. I am not saying changing both is piss poor way to do things but there are scenario's where it doesn't necessarily need to be done.. but this requires the end user to have certain technical abilites most civilian end users just don't have... I know a Mopar dealer surely wont swap both batteries under warranty just because one crapped out..
and most people are just ignorant enough about this stuff to not know how to deal with this stuff, so they let their own insecurities get in the way of sound mechanical and financial reasoning...

I'll give you my own scenario and tell you why I am probably going to shi+can two known good batteries.
I plan on hauling my RV up to Tuktoyatak NWT this summer.
my battery's are 5 years old right now.
They show no sign of crapping out
but I plan on going somewhere where even buying a bag of potato chips might entail a 300 mile drive
so that is my plan.. replace known good used batteries for new batteries and hope they are as good as what is in there.
We all know some babies are born dead and some don't live very long... just the way it is.

but if I was just sticking around home, I'd wait until I knew I had a battery issue, then replace both as they are both the same age..

 

[petersonj]

I am not saying changing both is piss poor way to do things but there are scenario's where it doesn't necessarily need to be done..

Now I am in a dilemma..., what should I do with my 18 year old tractor battery? I'm sure glad I don't have a pair of them. Just kidding! I am going to see just how long it lasts.

I prefer to do real life battery load tests by using the engine starting motor. Below is an example of a load test with both batteries combined (from my maintenance log). The batteries at the time were four years old.

Both batteries fully charged and then disconnected for 30 hours. After 30 hours the following was recorded:

Right Battery - 12.90 volts disconnected
Left Battery - 12.93 volts disconnected

Remove Fuse 3 (engine control) Load Test batteries as a pair (two fifteen second cranking periods) Lowest voltage recorded at the end of each cranking period:

10.22 volts (batteries recovered to 12.55 volts within one minute)

Engine cranked steadily throughout each test cycle.

I ran these batteries for two more years.

When I deem necessary, I will load test each battery independently. I have always replaced batteries in pairs, but only because they always had years of operation before showing signs of problems. If, for some reason one new battery of a pair of new batteries failed in a few months, I would definitely consider replacing just the failed battery (after my testing, of course).

- John

 

[Grumpy8811]

Now I am in a dilemma..., what should I do with my 18 year old tractor battery? I'm sure glad I don't have a pair of them. Just kidding! I am going to see just how long it lasts.

- John

now that you mentioned tractor batteries. I inherited my Dads early 2000 compact John Deere and it had the original battery in it , so that thing lasted a good 15 years.. can't complain.. then again, even if it ever left me stranded it wasn't going to be like I was more than 500 feet from the house.

 

[Turbo Terry]

Grump it’s a long way to Tuktuyatak NWT. Hope you can haul a lot of fuel. I would go to Dawson or Whitehorse and fly up the for a day or two. B&B rent some wheels and explore . One thing I can share with you is you need to get a Canadian fuel card somehow. That’s where the big trucks fuel up and def etc

 

[Grumpy8811]

Grump it’s a long way to Tuktuyatak NWT. Hope you can haul a lot of fuel. I would go to Dawson or Whitehorse and fly up the for a day or two. B&B rent some wheels and explore . One thing I can share with you is you need to get a Canadian fuel card somehow. That’s where the big trucks fuel up and def etc

truck holds 92 gallons. Found out wish I had a PetroCanada fuel card already although reality is everybody takes the good old Visa..
I can imagine what fuel is going to cost on the Demptser, apparently there is Eagle Plains and Fort Mcpherson have places to buy some.
We were in Coldfoot AK and fuel was $750 a gallon, so its probably 250 a litre or more in Canada on the Demptster.

I did Alaska, Whitehorse and Dawson City already once already,
actually have been up the Dempster without the RV, to maybe 50 miles north of the Tombstone Territorial Park.
I don't need DEF anymore. LOL..

 

[Signal73]

truck holds 92 gallons. Found out wish I had a PetroCanada fuel card already although reality is everybody takes the good old Visa..
I can imagine what fuel is going to cost on the Demptser, apparently there is Eagle Plains and Fort Mcpherson have places to buy some.
We were in Coldfoot AK and fuel was $750 a gallon, so its probably 250 a litre or more in Canada on the Demptster.

I did Alaska, Whitehorse and Dawson City already once already,
actually have been up the Dempster without the RV, to maybe 50 miles north of the Tombstone Territorial Park.
I don't need DEF anymore. LOL..

$750 a gallon???
$7.50 I presume?