My 1st thought was also that I was in low range, but I can definately feel the shift as I go from low to high, and can also note the rpm change. I have even been a bit creative and tried some split shifting (using the transmission and 2 speed in combination shifting).
The thought of a governor had occured to me, so I will check that out.
KB3csw, I am sure you are thinking of Harry's U-Pull-It; the place isn't all that far from me, and I even know a guy who used to work there, so that is a good lead.
Rick, thanks for the affirmation. Although it has been almost 40 years since I drove that old reefer, I knew she did better than my present 35-38 mph.
Sam
52 Chevrolet 2 ton (Schuyler)