TMC is an independent, primarily volunteer organization that relies on ad revenue to cover its operating costs. Please consider whitelisting TMC on your ad blocker and becoming a Supporting Member. For more info: Support TMC

Snow chains for Model S with 21" turbine wheels?

Discussion in 'Model S: Driving Dynamics' started by badlydrawnboy, Feb 4, 2017.

Tags:
  1. badlydrawnboy

    badlydrawnboy Member

    Joined:
    Jun 9, 2016
    Messages:
    30
    Location:
    Berkeley, CA
    I'm planning a trip to Tahoe from the Bay Area in a couple of weeks. Have a Model S 90D with 21" turbine wheels and all-seasons tires. My understanding is that the 90D performs very well in the snow without chains, but that in California there is a legal requirement to carry chains in the car. I've heard that a couple of Model S drivers have been forced to put their chains on at "chain control" checkpoints.

    This seems like a potential problem because as far as I can tell the Tesla recommended chains only fit on 19" wheels? And from what I've read they're already pretty hard to install on those wheels.

    What are my options here?
     
  2. badlydrawnboy

    badlydrawnboy Member

    Joined:
    Jun 9, 2016
    Messages:
    30
    Location:
    Berkeley, CA
    I did a little more research about the three different requirements.

    R1: 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 must be carried by vehicles using snow tires.

    R2: Chains are required on all vehicles except four-wheel-drive vehicles under 6,500 pounds gross weight and equipped with snow tires on all four wheels. Chains for one set of drive wheels must be carried by four wheel-drive vehicles using snow tires.

    R3: Chains are required on all vehicles without exception.

    Apparently R3 is rare and roads are often closed before it is imposed.

    According to my reading of this, a car with AWD and snow tires on all 4 wheels would rarely be required to put chains on.

    So here's the key question: would the "all-seasons" tires I have on my MS considered "snow tires" by chain control checkpoints?
     
  3. abasile

    abasile Independent Software Eng.

    Joined:
    Oct 21, 2012
    Messages:
    533
    Location:
    San Bernardino Mts., CA (Elev. 6100' / 1800m)
    #3 abasile, Feb 4, 2017
    Last edited: Feb 4, 2017
    I would agree with this. AWD is generally your "ticket" to get past those chain control checkpoints without hassling with chains. However, all vehicles are legally required to carry chains when driving in the California mountains during winter. Even if you have AWD, be prepared to be asked at the checkpoints if you are carrying chains. Legally, you need to have a set of chains that fit your tires. The authorities may turn you around and/or issue a ticket if you don't have chains.

    Your tires need to have the M+S rating to be considered snow tires. The Goodyear Eagle "all season" tires that came with my Model S have this rating.

    My experience, from living in the SoCal mountains, is that chains may be required (R2) at the slightest bit of white on our mountain highways. The authorities assume that a great many drivers have no clue about driving on snow and ice, and considering that we are in California, that's a fair assumption. Currently, requiring vehicles to have AWD or install chains seems to be enough of a filter to minimize crazy behavior on snowy roads. If all vehicles were to come with AWD, then the authorities would probably have to come up with a different filter. In any case, carrying around a set of chains is necessary to play their game, regardless of whether you'll truly ever need them.

    Personally, I wish California could do away with this AWD vs. 2WD nonsense and allow drivers to get tested for snow driving aptitude. Then, having a "snow driving" endorsement on one's license should be enough to get past the checkpoints most of the time, provided one's car at least has M+S tires in good condition. The thing about AWD is that, while it helps you get moving, it doesn't help you to come to a stop.
     
  4. badlydrawnboy

    badlydrawnboy Member

    Joined:
    Jun 9, 2016
    Messages:
    30
    Location:
    Berkeley, CA
    Thanks. So I guess the question is what chains should I buy, given that there aren't any that fit the MS 21" wheels (as far as I know)?
     
  5. rdr1rx

    rdr1rx Member

    Joined:
    May 10, 2016
    Messages:
    32
    Location:
    Bay Area, CA
    The 21" tires available for Model S are either winter compound (245/35R21 only) or max performance summer compound (245/35R21 & 265/35R21). Can you post a pic of your tire sidewall & tread? I'm curious to see what manufacturer makes said 21" all-season tire.
     
  6. badlydrawnboy

    badlydrawnboy Member

    Joined:
    Jun 9, 2016
    Messages:
    30
    Location:
    Berkeley, CA
    You are correct and I was mistaken; I have the summer performance tires. It seems the best option for me is to get the 20" TST wheels and then the Continental DSW 06 all-seasons tires. This will preserve (as closely as possible) the look of my 21" grey turbine wheels while allowing me to get all-season tires.

    It will cost me a little over $3k with installation, but I'm hoping I can sell my 21" wheels/tires on the used market to offset the cost at least a bit.
     
  7. AMPd

    AMPd Active Member

    Joined:
    Nov 27, 2012
    Messages:
    1,850
    Location:
    Northern California
    Or you can get winter tires for your 21s for the winter season.
     
  8. badlydrawnboy

    badlydrawnboy Member

    Joined:
    Jun 9, 2016
    Messages:
    30
    Location:
    Berkeley, CA
    I live in the SF Bay Area, where winter tires are completely unnecessary. I only need them for the 2-3 trips we take to Tahoe during the ski season. It would be time-consuming and expensive to change back and forth between summer/winter tires for these trips, so I'd prefer to just spend the money up front and have all seasons tires.
     
  9. tmarcc

    tmarcc Member

    Joined:
    Jul 25, 2016
    Messages:
    70
    Location:
    Los Angeles
    So there's no option at all for chains on the 21" wheels? Afaik Tesla clearly instructs "no chains for 21" wheels" in their manual, but I'm curious as to whether anyone here on the forum has tried it.
     

Share This Page