The 18 gallon tank makes towing a problem. That's about 14 useable gallons. Towing a 5k lbs travel trailer will likely result in 7-9mpg. At an average of 8mpg, it is 112 miles of range. That's not enough range to get between gas stations in places on the current interstate highway system. It would make an Alcan trip very challenging. There were times I was concerned with 38 gallons in my Tundra. So, it'll require hauling gas cans around if you want to tow very much. That's do-able, just a pain in the ass in an SUV. In a truck like a Taco - it's much less inconvenient. Gas cans in the bed are easy. I think the solution for me would be jerry cans mounted on the tongue of the trailer so they can be re-filled easily when refueling and are pretty convenient to fill up the gas tank when you run out.

Other markets do get an OEM aux tank in this platform that combine to 30 gallons.