I am suppose to haul 14 tons on my tandem, I usually haul 15 to 15 1/2 tons, if I added a lift axle I think I could haul 18 tons, so every 5th trip would be a freebie if I had a triaxle. I am not sure how much weight a lift axle would weigh, I am basing my numbers on what a friend of mine can do with his Mack triaxle. My truck is heavy, unloaded it weighs 23200 lbs according to the scales at the quarry. If triaxles and quads have not made it to south Texas, you could be the first kid on the block If I had a triaxle I could run my truck more than I do. For asphalt around here you have to at least have a triaxle, quad would be better.