Trade journals such as Heavy Duty Trucking, which has been around longer than I have, has always had articles about operating trucks efficiently. Back in the 50's and 60's, when 2 speeds were common, there were many articles written suggesting not to split shift a 2 speed on an empty truck to save fuel and to save wear and tear on the drive line. Two speeds are much harder to shift smoothly on an empty truck than a loaded one. We had 2000 four compartment steel tanks with a pump and meter on our bob tails in those days. They probably weighed empty what Tim's vehicle will weigh with a pickup or suburban. We never split shifted them when they were empty. It was a sign of a kid just learning to drive by splitting the gears. I was guilty of that my self when I was 15 or so. By the time I was 16 and got my commercial license on my birthday, I was driving like the experienced drivers. My first semi was a 550 GMC with a 5 and 2. After I put a Neway drag axle, I weighed about 24,000 with an empty trailer. I usually only split 4th and 5th gear when I was empty.
