It made a big difference when I switched from the crappy-in-snow though smooth-riding GY Eagle GAs to Wintermark MagnaGrip snow tires on my '04 Malibu Classic. I am in the foothills of the Poconos in Northeast PA. We don't get the snow you do, but we get plenty of sleet, slop and freezing rain, plus the transplants with SUVs who can't drive in winter.
However, my ride is two generations and three wheel sizes removed from your LTZ. If I were you I would get winter tires unless you only drive in the city or on the interstate, seldom at night and you can take off from work if needed if it's icy.
Note that your Eagle LS tires, like my old Eagle GAs, are designed for smoothness and comfort rather than wet/snow traction. See the GY Web Site and tirerack for more on that. Also, wide low-profile tires such as yours tend not to do well in snow. (Unless they are dedicated winter tires.)
If you plan to drive this car through Erie winters for many years, perhaps you should buy 4 steel wheels with winter tires mounted on them, maybe 16" or 17". You might have to buy tire pressure monitors, too. Someone else can advise you there. My buggy is so old I need not worry about such things.
A near-exact match in revs per mile would be 205/65/16, but I'm not sure 65-series tires would fit on an LTZ. (They do on an LS or LT, at least up to and including '08; not sure if things changed when the lower trims went to 55-series 17" for '09.)
215/60/16 should work, or 215/55/17 if you want bigger wheels. The speedo might be very slightly off, but I doubt by enough to fool the ABS computer or TPMS. Again, I can't advise you on that from first-hand knowledge.
The MagnaGrip is fully OK as a winter tire, but to protect a newish LTZ I would look at Nokians or Blizzaks in hard-core snow tires, or Michelin Alpin in performance-winter.
I've run Nokians Hakka RSIs and recommend them highly, with the caveat that they wear fast on bare pavement, no matter how cold. I have a friend who loves the Michelins for his highway commute; I've never run Blizzaks but as you know they have a great rep.
YMMV. Check out tirerack, discounttire, GY, Nokian, etc. on the Web. Good luck.
Regards,
Eric in PA
'04 Malibu Classic, white
2.2L Ecotec
