Automobile Magazine notes that Michigan has very few requirements for someone to get licensed to pull a vehicle and up to two trailers as long as, but more difficult to maneuver than, a semi-truck for which one would need to have a CDL license with far stricter requirements.
 

As a perk for living in the Water Winter Wonderland, Michigan allows drivers to attain an R – or “Recreational Double” – endorsement, allowing pickups to simultaneously pull a fifth-wheel travel trailer and a second trailer. There are some caveats, mind you – the total combined length can’t exceed 65 feet, and the truck must “have a towing rate equal to or greater than the total weight being towed.” Draconian, huh?

Here’s the best part: unlike CDL or even motorcycle endorsements, there is no skills test required. No, though you’ll be piloting a rig that’s longer than the articulated buses that drive past the state capitol in Lansing, the Secretary of State deems a road test to be unnecessary. As one clerk at the SOS office put it, it all “seems a bit unsafe.”

In Michigan, all that’s asked of you is to “pass” a simple fifteen-question test – miss three, and you’re still in the running for the endorsement. Miss four or more, and get back in line to take it again – you’re allowed a couple passes at it in a single day.

To pull a single semi-truck of similar length, but with only one point of separation between the cab and the trailer, you would need a full CDL license with specialized training and a skills test required. Some states require that you pass a road test to get such a license endorsement, while others actually require a full CDL license.