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Caltrans winter driving tips

Caltrans winter driving advice

submitted by Caltrans:

The California Department of Transportation (Caltrans) and the California Department of Highway Patrol (CHP) want you to get where you’re going safely this winter.  The following are some driving tips that will help you prepare for winter driving conditions:

Winterize your carCheck your brakes, windshield wipers, exhaust system and heater/defroster to make sure they are in good working condition.  Check your radiator fluid level and add antifreeze/coolant as needed. Replace wiper blades if needed.  Add a winter formula windshield wiper fluid. Make sure your tires are properly inflated and the tread is in good condition

Check road conditions frequently –During Storms, call 1-800 ROAD (7623) or check the internet at

Carry in your car – a flashlight with extra batteries, blanket, extra clothing, water and snacks, towel, gloves, ice scraper/deicer, shovel, small broom, spare key, sand/kitty litter.

Allow enough time  – Slow down.


Don’t panic – If you begin to slide while driving on snow or ice, slowly take your foot off the gas pedal and steer your vehicle in the direction you wish to travel.  If you must use brakes and your vehicle is equipped with anti-lock brakes (ABS), apply firm steady pressure.  If you do not have ABS brakes gently pump the brake pedal.  Do not allow the brakes to lock up.

 Black Ice Black ice is nearly invisible. The temperature doesn’t have to be below freezing in order for ice to form on road surfaces.  Ice can form, especially when it’s windy, when the air temperature drops below 40 degrees.   Low or shaded areas surrounded by landscaping or with a nearby source of water, such as bridges and underpasses, can have icy spots. 

 Be observant Do not pass snow removal equipment unless the operator directs you to.

 Stay with your vehicle – If you become stranded stay with your vehicle.  Conserve fuel while maintaining warmth and be aware of possible exhaust or carbon monoxide problems.

 ChainsAll vehicles, including those with four-wheel drive and snow tires are required to carry chains when traveling in areas that have chain control.  Make sure they are the correct size for your tires and in proper working order.  Chains must be installed on drive wheels.   Know if your vehicle has front or rear wheel drive.  Cable chains are acceptable, but may not provide as much traction as traditional chains. The speed limit when chains are required is 25, 30, or 35 MPH: it is posted and enforced.  Chain installers may be available to help install your chains.  They are not Caltrans employees.  They are independent business people who are licensed to install chains.  If you choose to use their services ask for a receipt that includes the installer’s badge number.  Chain installers are not allowed to sell or rent chains.  When removing chains or installing chains, drive beyond the signs reading “Chain Control/End Chain Control.”  Pull over out of the lanes of traffic.  

 Chain Control Information:
R-1 – Chains or snow tread tires with a tread depth of 6/32” and a “M&S”, “MS”, “M+S”, or “M/S” imprint on the tire’s sidewall.

R-2 – Chains required on all vehicles except four-wheel or all-wheel drives with snow tread tires on all four wheels.  Engage the four-wheel drive in the 4-high.    

R-3 – Chains required on all vehicles; no exceptions.

Tires – To find out if your tire tread depth is at least 6/32”, place a quarter into several tread grooves across a tire.  With George Washington’s head upright, if the bottom of his neck completely disappears, your tread depth is at least 6/32”.  If you can see any part of the bottom of George Washington’s neck, your tread depth is at or below 6/32” and should be checked.  Remember to check to make sure the tires have the imprint “M&S”, “MS”, “M+S”, or “M/S” which indicate the tire is rated for mud/snow conditions.  You may also see the mountain snowflake symbol on the tire. 

High winds and blowing snow often cause zero visibility conditions.  To protect travelers, the CHP may close the road temporarily until conditions improve.  During winter storms spinouts and accidents happen closing the highway.  Heavily traveled routes are particularly vulnerable to such closures.   Caltrans may meter traffic during the storm, letting fewer vehicles into the area reducing congestion and giving motorists the option of turning around and waiting out the delay in a warm place.

Cover Photo by Gary Young

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