Diesel fuel additive

[Rancher Rob]

I have a 2k gallon tank of diesel on the farm that I filled up about 8 years ago. When filling it, I put in a couple jugs of sta-bil. The fueling nozzle broke a couple years back and just last month (July 2019), I finally got around to fixing it so that I could use it again and the diesel is just fine. So I highly recommend the Sta-Bil.
Not so fun side note: Actually I had my son replace the nozzle but it seems there was a siphon lock going on and it kept pouring out diesel all over the place until I ran out there and started filling 5 gallon buckets until I could stop it! During that whole fiasco, I came across a yellow diesel can covered in dust in the barn that was half full of diesel from the same source company. It might have been a few years older than my big tank but wasn't treated and has now turned to paint varnish (you know that smell of really old bad diesel).

[valleyduo]

Change filters at least once a year and drain the water/sediment, and you really don't need any additives unless you will be exposed to sub zero temperatures. Been running diesels that way for over 20 years between trucks and tractors. Never failed me yet.

[FOURWHL]

I havent used any in 40k miles. Filters get changed twice a year.