I got tired of filling up my 26 gallon tank on my D-max and started doing some research on larger tanks. Obviously, GM didn't offer anything and didn't find anything until about a month ago. Titan Tanks makes larger tanks for all Diesels 99+. I'm having a 52 gallon installed today! Fewer runs to station, but its going to hurt when I do But at least it will help save some labor in the long run, I'll be able to fill up in the evenings or weekends and not have to worry about stopping in the middle of the day. Thought you guys might like the concept.