I just got my truck back from the dealer last night after dropping it off to check out the issue. Actually, I had (3) issues.
Anyway, the dealer said they scanned the truck and could not find any error codes (I didn't think they would after the check engine light intermittently came on and off and eventually cleared itself). They checked the battery and said no cells were damaged and the battery is at full charge.
I asked about the normal range for the voltage drop while driving. Mine usually hovers around 14.2-14.4. The Tech said a drop ~0.15 is considered normal. Now I am not so sure I heard him right because I had my voltage gauge display on and while I drove away, the voltage dropped to 13.4 which is a lot more than a .15 drop; this is exactly what it did during my battery issue in Colorado and when the check engine light would come back on. It is now back up to 14.2.
I had told the dealer about online reports of this happening to numerous 1500 and 2500 trucks. I also told them that a normal car jump did nothing and had to call roadside service. He wasn't interested much in any of that since their electronic checks showed nothing wrong. I am pretty sure he didn't take any time to investigate himself.
BTW, they couldn't duplicate my other (2) issues either, and so enough they resurfaced as I drove away. If I didn't have to go pick up dinner for the family, I would turned around and drove right back to the dealer.
Sorry this is of no help for you! I am at the point of seriously considering getting rid of the truck. Since I do a lot of road trips into the mountains, and lots of desert and mountain off-roading, I can't be worried about not making it back out. I simply don't trust the truck (with the battery and weird squeaking noises from the rear) and I have no faith in the service support to help me figure it out. So frustrating and now got me thinking about getting rid of my truck (would love the excuse to get a Power Wagon but probably not without knowing what the heck is going on with Ram trucks).
Edit: researched "normal" voltage drops while driving and it seems that it varies greatly depending on vehicle, alternator, etc. but my drop of up to 1.0 seems to be within the typical range. So now wondering if the Tech meant (or actually said) a drop of 1.5 is normal, not .15. Similar issues in this thread with some good explanation of Ram's modern charging system:
Wife and I are on a trip, 6 hours from home. 19 1500, 1 year old with 12K miles. My truck battery voltage has read consistently at 14.3 since purchased. While driving today, I noticed the battery bar gauge that I have on the dash looked a little lower than usual so I pulled the battery...
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