Did a search but came up with nothing, maybe the way I wrote it. Got some old diesel fuel in my MH. Last time we used it was 2015. Some time after that I put about 20 gals in it and now it has about ...
The new ULSD diesel is not the same as the old diesel. It does breakdown sooner and is susceptible to absorbing moisture, which shouldn't be a huge problem in AZ. It is a good idea to always keep the fuel tank as full as possible if you are going to let it sit for any length of time. I would fill up at the closest station and keep an eye on the fuel filters. You might want to put in a can of diesel additive to combat any algae that may have formed.