Do not use summer tires where the temps. go below freezing regardless of snow conditions. Summer tires lose allot of traction when the temps. get cold because the rubber hardens, a dangerous condition.
If you don't want to swap out tires for winter your better off getting an A/S tire that leans towards dry performance over snow traction like the Michelin Pilot A/S plus but then you have the run flat issue since it's not available in a run flat version in our size. I had them on my Audi S5 and they were good in the dry and rain but just fair in snow.
What I'm thinking of doing like "djsilo" mentioned is getting a 45 series tire since I've had many bubble problems with the Goodyear LS2 245/40/19 tires. I'm looking at the Bridgestone Potenza RE-960-AS Pole Position run flat which comes in 245/45/19 and is a newer design run flat compared to the Goodyears. I'm not sure if BMW will honor my wheel and tire insurance though if i don't use the original OEM tire. Why can't this be simple.
2011 550ix Alpine White, Black, 775, ZSP, ZDH, ZP2, 2TB, ZCW
2013 X5 35i Premium, Conv.pkg., Prem. sound, multi contour seats, cold weather pkg.
Porsche 997 GT3
Porsche 993 Cab
Porsche 996 Turbo (Ruf 550) gone but not forgotten
Last edited by Diver624; 12-09-2012 at 10:13 AM.