I don't want to scare you, but my C280 is a handful in the snow, even with snow tires. I have much older Blizzaks on it and just ordered a new set of WS60s today to hopefully make it easier to manage. The back end is just too light. I'd advise you get her a top quality set of winter tires and maybe even put some 200 lbs of something in the trunk to help get more traction. Use something that wont slide around, like a big bag of unmixed cement or salt or something like that.

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Jonathan

2011 Mazda2
2000 E320 4Matic Wagon
1994 C280 (retired)