AZ is so weird about diesel. I think I mentioned that in that other thread about fuel taxes. There is a station I like to use that has 2 "high flow" lanes (big nozzles) that semis can use (has nozzles on both sides), and one for regular flow with only a driver's side, small nozzle. The main fuel price sign shows $2.879 right now but then off to the side is a flip board number type of sign that says something like "light duty" price is $2.799. My RV falls under that lighter duty so I can get the price. But, it's a minor pain. You have to go inside, leave a card or something of "value" they say, so they can start the pump before you actually pay, then you go pump your fuel, then go back inside and pay how you want (cash or card), but also you have to provide your license plate number, print your name and sign your name in their notebook to get the cheaper price. I have all the time in the world so I go through the hassle. I filled both tanks today, just over 11.5gal in each, 23.04gal total, and the "discount" between the heavy taxed rate and light rate was $1.84. Yeah it's a pain, but that pays for over half a gallon. At 8mpg, it's worth he hassle to me. Plus I get another 2% cash back on fuel too, so that's another ~$1.30 I'll get back on the credit card. So between the "discount" and the 2%, I got a "free" gallon on this fill-up.