Easy fix to all problems you listed:
RAM (DS) EcoDiesel Compliant Engine & Trans Tune - GDE (greendieselengineering.com)
I had the same concerns when I initially purchased my 2018 Ecodiesel. Installed this...all better now.
Manual states that fuel filters have to be rated at 3 micron. I have not found and aftermarket fuel filter that has this rating. I have found some after markets filters that claim 4 micron. Probably would be ok, but these fuel systems are very sensitive and I personally would not chance it...
I was interested too. So I used my truck as my DD all last week.
477.7 miles @ 22.631 gallons = 21.1 MPG. This was a pretty even split between city/hwy driving
EVIC was slightly off and displayed 22.5 for that tank.
Got my EGR recall done yesterday. Have the EPA GDE tune. Put back to stock before I went in. Put back to GDE as soon as I got truck back. So far so good. No issues.
Dealer was really awesome about it. Service writer said they needed the truck all day and he put me in a 2020 Ram 1500...
Can be great trucks. Definitely figure out the coolant issue...stay on top of the dealer.
GDE tune highly recommended. The tune will give you back that HEMI feeling.
I almost never run unloaded. My daily driver is a VW Jetta TDI. The Ram is my weekend vehicle and is always pulling some type of trailer. If I ever burn through a full tank while unloaded, I will definately post.
Returned from my trip last night. Truck ran great. I was pulling 5,000lbs from FL to WV and back. (Family ATV trip to Hatfield & McCoy Trails)
Total hand calculated MPG for trip was: 17.1 (EVIC showed 17.9)
It is my opinion that Tow/haul mode was a must for this weight. Shift points are...
Ok friends. My new GDE emissions compliant tune is installed. Initial thoughts are very positive. Installation is very simple and straightforward. The instructions are spot on.
I immediately noticed the following:
Engine seems quieter
Shifts are much quicker
Holds 8th gear wayyyyy better...
2018 Laramie Crew 4x4 6'4 bed 3.55 rear
43,xxx miles. No issues.
Avg mpg 18.1, but that is almost strictly towing some type of load. Boat, jetskis, lawn trailer, etc. Hardly ever drive the truck unloaded. That is what the Jetta TDI is for!
Not tuned, but will be as soon as I get my new...