06 chevy aux fuel tank

The good ones are not cheap. I have an RDS 60 gallon tank that will fit under a cover. I use a small fuel pump (some say just gravity will do, and some say that it flows too slowly to keep up at times) and an electric shut-off valve (because the truck's ECM does not like being overfull for too long) and a nice illuminated switch (green for diesel) in the overhead console to energize the isolation valve and pump. Also an Auto Meter gauge for it, with matching red illumination, in the center console. It's a slick set-up and the total cost was around $800.00 for everything. I did the install myself.

I love it. 2000+ highway (23 mpg @ 70 mph) miles range unloaded. In town I fuel up every month or so.