M+S or Winter tires required in western U.S.?
I did a search of DOT websites. It appears M+S or winter (mountain-snowflake marked) tires are not required in WA, ID, MT, UT, CA, NV, AZ unless conditions warrant authorities to require them i.e....
Forum Discussion
rider997 wrote:
All vehicles (including 4WD) are required to carry chains in chain control areas at all times.
R2: Chains required on drive axle for 2WD vehicles. 4WD vehicles must have snow tires (mountain + snowflake symbol); "Mud+Snow" tires are NOT acceptable.
I don't think those 2 points are correct either. You can read the Caltrans page here: Caltrans Chain controls page
4WD/AWD vehicles must carry chains in R2 areas. It doesn't say that under the R1 restriction. It is advised to carry them in all areas subject to chain controls because you may have to backtrack if you get checked at an R2 screen, but I've never seen a checker at an R2 sign, and haven't seen one of those in about 20-years anyway.
M+S tires are considered snow tires for R2 purposes. Read the paragraph at the bottom of that link where it says "Snow-tread tires can be identified by examining the sidewall of the tire where the letters MS, M/S, M+S or the words MUD AND SNOW have been stamped into the sidewall."
I've never seen an R3.
These fine points are important to me because I have 3 4WD vehicles and no chains for any of them, and we drive in snow all the time. I'm certainly not advocating that practice, but I personally hate chains and avoid them at all costs!
