Hi, thanks for the add:
I have a 2016 RAM Cummins 3500 and my batteries are getting weak (Battery Saver Mode) message intermittant.
I have been told to buy only OEM batteries because these vehicles are voltage sensitive, is this a real concern? Also I was told the OEM batteries are 1000 CCA. verses aftermarket 800 CCA. can anyone provide some insight and recommendations.
Thank you,

 

You running group 65 batteries in the 16? Curious if you have checked for a poor/corroded ground? Dirty battery posts? Loose connections on the battery wiring? I have 2010 CTD 3500 and the battery posts are always getting corroded. I still have original batteries in the truck, but I hook-up the battery charger as I'm a cheap skate.

I was going to install group 31 batteries (real diesel batteries) when I get around to buying batteries.

 

If you dont like the corrosion on the posts then get batteries like the optima red tops,,, you will Never clean a post again. Any AGM battery will be corrosion free I put them in my 96 diesel back in 2006 and changed them in 2016 and never once had to clean a battery post

 

Or epoxy a couple copper washers on the top to act as a sacrificial anode to keep corrosion off the terminals.

 

If your batteries are bad i would go with what you feel comfortable with. But get them load tested first. I have never purchased an OEM battery in my life. OEM it just a brand they don't make their own batteries. I think there are only 3 battery manufacturers left . I could be wrong