Colorado’s commercial vehicle chain law goes into effect September 1

Commercial vehicle drivers passing through Colorado will need to start carrying chains as the state’s chain law goes into effect.

Colorado chain law goes into effect each year from September 1 to May 31 on the following roadways:

• I-70 west of milepost 259 (Morrison) to the Utah border.
• Colorado Highway 9 mile post 63 to milepost 97 (Frisco to Fairplay).
• Route 40 milepost 256 (Empire) to the Utah border.
• U.S. Route 50 milepost 225 (Salida) to the Utah border.
• U.S. Route 160 milepost 304 (Walsenburg) to the New Mexico border.
• U.S. Route 285 milepost 250 (Morrison) to the New Mexico border.
• All of U.S Route 550.

The law applied to vehicles used in commerce with a combined weight of more than 16,000 pounds or as transport for at least 16 passengers.

In years past, the Colorado State Patrol (CSP) has conducted regular chain checks to ensure compliance with the state’s chain law.

Penalties can include:

• $50+ for not carrying
• $500+ for not chaining up
• $1000+ for blocking as a result of not chaining up

Vehicles required to chain four drive tires:

• Straight Trucks: 4 tire chains, 4 AutoSocks, 4 tire cables 0.415 diameters or greater, auto chains, or sanders. 
• Single Drive Axle Combinations: 4 tire chains, 4 AutoSocks, auto chains, or sanders. No cables are allowed. 
• Tandem Drive Axle Combinations: 4 tire chains, 4 AutoSocks, 4 tire cables 0.415 diameter or greater, auto chains, or sanders. If chains are on the 2 outside tires of one drive axle, any tire cable may be used to cover 2 tires on the other drive axle. AutoSocks may be used to cover 2 tires on the other drive axle. AutoSocks and tire cables cannot be used together. 
• Auto Transporters: 4 tire chains, 4 AutoSocks, 4 tire cables 0.415 or greater, auto chains, or sanders. Do not use chains if use places hydraulic lines at risk of damage (alternative traction devices (ATDs) may be used to mitigate the risk). Travel will be restricted if the vehicle is unable to chain.

Vehicles required to chain two drive tires: 

• Buses: 2 tire chains, 2 tire cables 0.415 diameters or greater, 2 AutoSocks, auto chains, or sanders.
• Hot shot trucking: Traditional motor vehicles (such as pickup trucks) that are pulling trailers and meet the above-listed weight criteria must also carry chains. 2 tire chains for singles (to affix to rear tires). Exception: Duallies need 4 tire chains.