The weight limit for a class B driver's license is 3,500 kg. In terms of volume, the largest vehicle in our class B category is the 14m3 Crafter. This is a large van that can carry around 1150 kg of payload.
In general, the total weight of the vehicle (driver, passengers, cargo, fuel, etc.) must not exceed 3500 kg. If you overload the vehicle and are stopped by the police or the Norwegian Public Roads Administration, you can receive a fine of up to 5,000 NOK.
You can read more on the Norwegian Public Roads Administration's website as well: What are you allowed to drive?
Drive safely!