We do things a little differently here in Canada. ( where I live anyway) We don't look at the GVW of the vehicle but at the number of axles. Your non- commercial licence allows you to drive any 2 axle truck except for a 2 axle "power unit". "Power unit" usually being defined as a vehicle designed to have a 5th wheel mounted. Any air brake equipped vehicle ( including motorhomes etc) means the driver must have an air brake endorsement on his licence, except for farmers,fire apparatus, and "air over hydraulic " systems.
A class of "CDL" is needed for all 3 axle trucks (tandems), buses, and power unit/semitrailers.Also required for taxis, ambulance etc.
The biggest issue I've seen lately is not a straight truck but people who tow trailers in excess of 10,000 lbs (trailer and load). Most jurisdictions use this 10,000lbs towed as the basis for needing a "CDL" licence. Lots of people are out there driving their Duramax dually towing a 32 foot 5th wheel RV who are running illegally, usually because they don't know. Unfortunately ignorance of the law won't help them after a collision when they are being sued for everything they've got and their insurance company has denied coverage.
