Consider yourself lucky. The donut spare in my wife's 850 blew apart in the trunk (thru the tread not the sidewall) and almost caused a major accident. It had never even been out of the trunk! I replaced it with a fullsize 16" from TireRack, so now it is the same diameter as all the tires and no speed / mileage limitations on it if we have to use it. Those Firestone Donut Spares are a hazard and shouldn't even be in the car, let alone on it. You can get a brand new 16" rim (5 x 108mm bolt pattern) and Khumo V-rated tire (205/50-16), whole setup balanced, from TireRack.com for $160 and I think that included shipping. It fits in the stock trunk space fine but it sticks up about an inch, worth it to have a good spare back there. With my WeatherTech mat back there I don't even notice it. Everyone should check their spare tire, if its a Firestone get rid of it. Learn from my experience instead of finding out on the side of the road one night. Mike