The Stovebolt Site Forums The Parking Lot Big Bolts 16,000 GVW. What's the tonnage?

The Load Capacity Chart in my 56 shop manual list my 56 with a GVW of 18,000 pounds and a GCVW of 32,000 pounds. But the same truck with a Taskmaster V8 as the only change was rated at 19,500 GVW and 32,000 GCVW that doesn’t make much sense to me but that is how they where rated.
In case you may be wondering GCVW is Gross Combination Weight otherwise the total weight of truck and trailer in combination. One would think if a motor is good to pull 32,000 on a truck and trailer combo it should pull a truck at 19,500 but the manual plainly states same truck different motor.