Minnesota trailer laws and regulations
Minnesota trailer rules from DPS: 3,000 lb brake threshold, 4,000 lb title cutoffs, dimension limits and the breakaway rule for heavier rigs.
In Minnesota, the brake line is 3,000 lb gross weight. At or above that, you need trailer brakes that can stop and hold the rig, and those brakes have to engage automatically if the trailer breaks loose. The title cutoff sits at 4,000 lb GVWR (or 4,500 lb for utility, boat and snowmobile trailers), and every trailer using a public road has to be registered through DPS-DVS.
Statute Minnesota 169.67 is where the brake and breakaway rules live, in case you need to pull the exact language. The numbers below are the ones a typical tower hits.
Quick reference
| Item | Minnesota rule |
|---|---|
| Registration | All trailers on public roads |
| Title required | Trailers over 4,000 lb GVWR (4,500 lb for utility, boat, snowmobile) |
| Brakes required | Trailers 3,000 lb GVW or more |
| Breakaway brakes | Trailers over 6,000 lb empty |
| Max combo length | 60 ft |
| Max trailer length | 45 ft |
| Max width | 102 in |
| Max height | 13 ft 6 in |
| Max hitch length | 15 ft |
| Mirror visibility | 200 ft to the rear |
Registration and titles
Every trailer that touches a Minnesota public road has to be registered with the Department of Public Safety, Driver and Vehicle Services (DPS-DVS). The license plate has to be mounted on the rear and visible.
Title rules depend on the trailer type. A general trailer under 4,000 lb GVWR doesn’t need a title unless there’s a lien. Utility, boat and snowmobile trailers under 4,500 lb GVWR are also title-exempt. The registration card serves as proof of ownership in those cases.
Farm trailers can skip registration in many cases. Other trailers run a $300 fine if the plate isn’t visible.
General towing rules
You can’t ride in a trailer being towed on a Minnesota highway.
Dimensions
The trailer body maxes out at 45 ft. The tow vehicle plus trailer combination can’t push past 60 ft. Width is 102 inches and height is 13 ft 6 in.
Maximum gross weight is 80,000 lb provided you stay within axle limits (the 7-ton single-axle cap applies on most roads).
Hitches and connections
The hitch or other connecting device between two vehicles can’t exceed 15 ft.
Lighting rules
Trailers and semi-trailers built after 1960 need two rear red lamps visible from at least 500 ft, plus at least two reflectors mounted 20 to 60 inches off the road surface and visible from 50 to 300 ft behind the trailer. (The original copy said “20 to 20 inches”, which was a typo in the source.)
Pre-1960 trailers can get by with one properly mounted rear lamp.
Speed limits while towing
No separate towing speed. Posted limits apply. As with every state, a swaying or out-of-control trailer at the speed limit is its own ticket.
Mirror rules
If your trailer or load blocks the rear view, you need a mirror that gives at least 200 ft of visibility behind the last towed unit. On wide loads, that usually means extender mirrors or factory tow mirrors.
Brake rules
Trailers and semi-trailers with a gross weight of 3,000 lb or more (or a gross weight that exceeds the empty weight of the tow vehicle) need brakes capable of controlling, stopping and holding the trailer. Those brakes also have to engage automatically if the trailer breaks away.
Trailers over 6,000 lb empty need a brake system that can hold the trailer stopped on its own if it separates from the tow vehicle. In practice that means a breakaway battery and switch, which is standard equipment on anything sold with electric brakes.