I drove a later KW with a "fuel squeezer" Cummins in it. Car drivers would give me the finger going up even the slight grade though downtown Seattle. I named that hill Hotel Hill. I could make 18 MPH pulling 80,000 lbs. of special Mt Rainier glacier water. Nordstrom's sold it for $4 per pint. Somebody made a lot of money on that haul and it wasn't me.
It was slower than the 170 Mack Thermodyne I once hauled hay with. I think it had an 8 speed. The company had two of them. Eventually the shop turned one of them up with bigger injectors and a higher wastegate pressure. One really had to watch the pyrometer after that. It didn't last long before somebody stuck a cylinder liner. Fortunately this was a an hourly trip not mileage. The only saving grace to that trip was that it was a trip to the woods by Mt Rainier and very pretty. I used a trash pump to load 6,000 gallons from the Carbon River. Just run the pump till water blew out the domes on top then shut it off.
