Under the Colorado Chain Law, a commercial vehicle is defined as being used in commerce to transport passengers or property and fitting into you of the following categories:
• Has a gross combination weight rating of 26,001 or more lbs. inclusive of a towed unit which has a gross vehicle weight rating of more than 10,000lbs.
• Has a gross vehicle weight rating of 26,001 or more lbs.
• Is designed to transport 16 or more passengers, including the driver
Colorado’s CHAIN LAW REQUIRES Commercial Vehicles to have Tire Chains or an approved traction device in the vehicle from Sept. 1 to May 31 while on the I70 Corridor, from Dotsero (MM 133) to Golden (MM 259).
Colorado’s CHAIN LAW REQUIRES Commercial Vehicles to have 4 or more drive wheels covered with an appropriate traction device. (Except Busses)
Straight Trucks
Are allowed to use 4 tire cables as long as they are 0.415” in diameter or greater; 4 tire chains; 4 autosocks; auto chains or sanders, covering 4 drive tires.
Single Drive Axle Combinations
Are allowed to use 4 tire chains; 4 autosocks; auto chains or sanders covering 4 drive tires. NO CABLES ALLOWED
Tandem Drive Axle Combinations
Are allowed to use 4 tire chains; 4 autosocks; 4 tire cables 0.415 or greater; auto chains or sanders covering 4 drive tires. * IF there are chains on the 2 outside tires of one of the drive axles, any type of tire cable may be used to cover the other 2 tires. Autosocks may also be used to cover the other 2 tires. Autosocks and tire cables CAN’T be used together
If you are interested in busses, the information is in the attached PDF

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