Cartoon by https://newsie.social/@royaards
In the US at least, you need a CDL if you drive a vehicle with a gross vehicle weight greater than 10,000 lbs (4536 kg). The 2022 GMC Hummer EV weighs a whopping 9,063 lbs (4111 kg) so that’s probably the largest vehicle a regular person would be able to buy.
I’m 99% sure it’s 26,000lbs at least for a straight truck non combination.
Source: I used to be a CDL A holder
Commercial motor vehicle: means any self-propelled or towed motor vehicle used on a highway in interstate commerce to transport passengers or property when the vehicle—
(1) Has a gross vehicle weight rating or gross combination weight rating, or gross vehicle weight or gross combination weight, of 4,536 kg (10,001 pounds) or more, whichever is greater; or
(2) Is designed or used to transport more than 8 passengers (including the driver) for compensation; or
(3) Is designed or used to transport more than 15 passengers, including the driver, and is not used to transport passengers for compensation; or
(4) Is used in transporting material found by the Secretary of Transportation to be hazardous under 49 U.S.C. 5103 and transported in a quantity requiring placarding under regulations prescribed by the Secretary under 49 CFR, subtitle B, chapter I, subchapter C.
That only matters if you’re “for hire”. I’m not aware of a single state or province where you can’t drive a 45 foot long tour bus RV towing a double car trailer on a regular license. You can legally b-train trailers in lots of places. Giant truck + huge trailer + cargo trailer full of quads and side by sides is totally kosher.
Edit: I can go buy a Ford F750 and drive it like a pickup truck if I want. The Hummer is not nearly the biggest vehicle a normal person can buy and drive