Hello all, I'm a new member of your forum but wanted to post a link to my current post "Lithium Upgrade with 630AH of Lithionics Batteries (https://sprinter-source.com/forums/index.php?threads/91673/)" on my early model, 2015 MB24. I previously made several other step-by-step posts including installing a 25-gallon auxiliary water tank for a total water capacity of 50 gallons. I believe you might need to be become a member or guest to actually view the pictures. If you have difficulties, PM me, and I can send you a PDF file of the installation instead. Feel free to share the post if you wish.
I have a ‘19 UMB and am interested in your 25 gallon water tank upgrade. Can’t seem to find a link on the site. Your write up on your battery upgrade is very impressive. Most likely will do that at a later date.
Keep in mind that the extra 25 gal of water adds 208 lbs. These Sprinter based RVs don't have much extra cargo carrying capacity. It is easy to overload the GVWR with just normal boondocking gear, liquids, and passengers.