Let's see ... the ONLY thing that's stranded me on my 2018 RAM Cummins pickup has been bad batteries. Three Times. Two jump packs are not enough to start the truck.
No, you don't replace batteries in pairs "just for fun". Do you think needing a jump start and another circus to replace batteries is fun? It's a $100-200 battery they wish to not replace as a pair.
It's an accepted industry standard to replace batteries in pairs. This is literally NOT doing it right the first time PERIOD.
ONE OF THE MANY RESPONSIBILITIES I INHERITED AT MY OLD JOB WAS SOMEHOW I ENDED UP BEING THE BATTERY GUY. I DEAL WITH THE VENDORS, THE MECHANICS AT THE JOB AND THE INBETWEEN BETWEEN MANAGEMENT AND WHOEVER. OUR VEHICLES HAD 4 GROUP 31 BATTERIES, MY EMPLOYER INSISTED ON AONE YEAR WARRANTY,AND SINCE WE HAD 700+ VEHICLES WITH HUGE PARASITIC LOADS WE WENT THRU BATTERIES LIKE CRAZY.
WHAT YOU TERM IS AN INDUSTRY STANDARD IS REALLY MORE OF A INDUSTRY SUGGESTION.. IT DOESN'T HELP YOU, BUT TO PROPERLY WARRANTY A BATTERY THEY HAVE TO CHARGE AND TEST IT. I DEALT WITH THIS END OF THE SUPPLY CHAIN MYSELF AND AT SOME POINT I BEGAN TO TERM THE BATTERY WARRANTY PROGRAM "THE BATTERY ROTATION PROGRAM" AS WHAT WE THOUGHT WERE DEAD WOULD GET SENT TO THE MANUFACTURER WHO WOULD CHARGE THEM AND TEST THEM AND SEND HALF OF THEM BACK AS BEING "OK".
So you drop in
a new battery and the tested good "older used" battery starts to murder the new battery.
REALISTICALLY, FROM A ELECTRICAL STANDPOINT, ONE BATTERY DOESN'T MURDER THE OTHER BATTERY UNLESS SOMETHING IS WRONG WITH THE ONE OF THEM.. ELECTRICITY FOLLOWS THE PATH OF LEAST RESISTANCE AND TRAVELS FROM A HIGHER VOLTAGE POINT TO A LOWER VOLTAGE POINT, SO ONE GOOD USED BATTERY THAT TESTS OK AND HOLDS 12.6 VOLTS STATIC CHARGE WON'T DRAIN ELECTRICITY FROM A NEWER BATTERY THAT IS ALSO 12.6 VOLTS. A AUTO BATTERY IS 6 CELLS ARRANGED IN SERIES AND WHEN FULLY CHARGED EACH CELL IS 2.1 VDC,HENCE A LEAD ACID BATTERY WITH 6 GOOD CELLS IS 12.6 VOLTS. IF IT HAS A BAD CELL IT WILL BE 10.1 VDC WHEN FULLY CHARGED, BUT THIS CAN'T BE DETERMINED ACCURATELY WITHOUT A CHARGE AND A LOAD TEST.
After the dealer warranted only one battery... I told my service advisor to replace the other battery and I would pay for it. ( Dealers charge labor to replace a battery where parts stores and battery stores do not. ) They didn't replace it. I fired my service advisor after a conversation with the service manager about not doing what they were told to do: On. My. Dime. Of course after I went over to Batteries Plus and replaced both with Odyssey AGM's (as they were having trouble getting X2's in).
THIS I DON'T UNDERSTAND ON THE DEALER'S PART, WHY WOULD THE DEALER NOT REPLACE YOUR BATTERY IF YOU WANTED TO PAY FOR IT?.
THEY MUST BE IDIOTS, CUSTOMER PAY IS GOOD MONEY AND I CAN'TIMAGINE HOW MUCH A PERSON WOULD PAY FOR A BATTERY AND INSTALLATION AT THE MOPAR DEALER .
This is after RAM needlessly needs the pickup for two days to run the extensive charging tests. The parts store tester can tell me in 30 seconds if it's bad. 5 min if they have to pull a cable off a dual battery setup.
NO ONE CAN PROPERLY TEST A BATTERY UNLESS AN ATTEMPT TO CHARGE IT HAS OCCURED FIRST . THAT IS ALWAYS IN THE BATTERY TESTING LITERATURE. THE DEALER MAY ACTUALLY USE A CARBON PILE FOR BATTERY TESTING,WHICH IS A FAR BETTER METHOD OF TESTING A BATTERY THAN THE ELECTRONIC TESTER THE AUTO PARTS USES. BACK IN THE DAY OF DELCO FREEDOM BATTERY'S, I ATTENDED A OEM CLASS FROM DELCO, AND THE REP INSISTED NOT TO GIVE UP ON A BATTERY SIMPLY BECAUSE IT APPEARED DISCHARGED..I FOUND OUT OVER TIME THAT WAS ACCURATE, SOME BATTERIES THAT ARE SEVERELY DISCHARGED CAN TAKE SEVERAL DAYS OF CHARGING BEFORE THEY WILL ACTUALLY ACCEPT THE CHARGE. ELECTRICALLY, THE MORE DISCHARGED AN AUTO BATTERY IS, THE MORE RESISTANT IT IS TO CHARGING...
So you drop in
a new battery and the tested good "older used" battery starts to murder the new battery.
ONLY IF SOMETHING IS WRONG WITH THE USED BATTERY. ITS EITHER 12.6 VDC WHEN FULLY CHARGED OR IT IS NOT.. IT DOESN'T MATTER IF THE BATTERY'S CAPACITY IS LOWER THAN ABRAND NEW BATTERY, IN RELATION TO COLD CRANKING AMPS, IT IS THE DIFFERENCE IN ELECTRICAL POTENTIAL AND NOT ITS AMP HOUR RATING OR CCA THAT DETERMINES WHETHER CURRENT WILL FLOW BETWEEN ONE BATTERY AND THE OTHER.
AT SOME POINT I WOULD THINK IF YOU WENT THRU 3 SETS OF BATTERY'S IN 6 YEARS, EITHER YOU ARE DOING SOMETHING WRONG OR THERE IS AN ELECTRIC PROBLEM IN THE TRUCK THAT ENDS UP WITH DISCHARGED BATTERIES,WHICH IS SYMPTOM, NOT THE CAUSE.HOPE THIS HELPS
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