If you are solid driving in mud, snow and ice and have a vehicle with good snow or off road tires, you'll be fine. I would not expect your typical AWD rental to have adequate tires.
You need 4 wheel drive to get to the springs in winter. Do not attempt the drive without 4wd, use the shuttle service instead.
Ice and snow, hills and mud combined are very slickery. If your unfamiliar with ice/snow/mud and how to drive on them, if plan on not going attempting on driving on them. Ice and snow, hills and mud combined with unfamiliarity with where your headed will make an interesting drive, and a bundle of money for a towing company. Hope tjat you took out rental insurance.
I haven't been to the springs in the dead of winter but I would recommend taking the shuttle, unless you're feeling adventurous. But if you aren't used to driving in snow, esp in the mtns, then I would highly recommend the shuttle or chains.
Yes please do not do it. You can buy tire chains.
Awd ought to be okay, assuming it hasn't recently snowed. Just drive reasonably.
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