California Chain Controls Explained: R1, R2, R3 and Live Pass Status
What each chain control level means for your vehicle, and which mountain passes have controls right now.
Chain controls on mountain passes right now
Conway SummitNo chain controlsUS-395 · Updated - Deadman SummitNo chain controlsUS-395 · Updated
Echo SummitNo chain controlsUS-50 · Updated 
Donner PassNo chain controlsI-80 · Updated - Sherwin SummitNo chain controlsUS-395 · Updated
Fredonyer PassNo chain controlsSR-36 · Updated 
Tejon PassNo chain controlsI-5 · Updated 
Tehachapi PassChain control status not available right nowSR-58 · Updated 
Cajon PassNo chain controlsI-15 · Updated 
San Gorgonio PassChain control status not available right nowI-10 · Updated 
Pacheco PassChain control status not available right nowSR-152 · Updated
Official sources can disagree. We show only data updated in the last 30 minutes—check the live camera.
What R1, R2 and R3 mean
Chains are required on all vehicles except passenger vehicles and light-duty trucks under 6,000 pounds gross weight and equipped with snow tires on at least two drive wheels.
Chains or traction devices are required on all vehicles except four-wheel/all-wheel drive vehicles with snow-tread tires on all four wheels.
Chains or traction devices are required on all vehicles, no exceptions.
Wording from Caltrans: Chain Controls. R-2C is treated as R-2.
Does my vehicle need chains?
| Your vehicle | R1 | R2 | R3 |
|---|---|---|---|
| Passenger car, no snow tires | Chains required | Chains or traction devices required | Chains or traction devices required |
| Passenger car or light truck with snow tires (M+S or similar marking) on the drive wheelsUnder 6,000 lb gross weight | No chains needed, but you must carry chains | Chains or traction devices required | Chains or traction devices required |
| 4WD/AWD with snow-tread tires on all four wheels | No chains needed, but you must carry chains (under 6,000 lb gross weight) | No chains needed, but you must carry traction devices | Chains or traction devices required |
| 4WD/AWD without snow-tread tires on all four wheels | Chains required, unless it has snow tires on at least two drive wheels and is under 6,000 lb (then no chains needed, but you must carry chains) | Chains or traction devices required | Chains or traction devices required |
| Any vehicle towing a trailer | Chains required on one drive axle of the towing vehicle. A trailer with brakes also needs chains on at least one axle. | ||
A summary of the Caltrans rules above, not legal advice. Signs and officers on the road decide what applies to you.
Good to know
- Snow tires have "MS", "M/S", "M+S" or "MUD AND SNOW" marked on the sidewall. Check before you leave.
- Expect a speed limit of 25 or 30 mph while chains are required.
- You can pay someone at the roadside to put your chains on. They are independent businesses, not Caltrans employees. They cannot sell or rent you chains.
- Ask for a receipt and the installer's badge number.
- Not following a chain control can get you a ticket from the California Highway Patrol.
Renting a car
Caltrans has no rental-car exception to chain controls. Check your rental agreement—many rental companies restrict chain use.
Source: Caltrans. Live status comes from Caltrans data and can lag behind the road. This page is general information, not legal advice; always follow posted signs and officers.