I had one of those on my truck, the problem you will have trying to use it by itself is it is a gravity feed tank, there is no pickup and it drains at the front. That means every time you try to climb a hill you'll run out of gas even if it is full. I used to watch my guage go from full to almost empty even with both tanks. When using it in conjuncton with the oem tank when you go downhill all the fuel drains to the main tank and when you are climbing all the fuel drains to the auxillary tank. It's great when both are full but anything at 1/2 in the main tank when you start climbing you could run out even though you have gas. My brother had one too and he ran out trying to climb Miller's Jeep slide.
