Okay, maybe this is a stupid question but I really don't know anything about tires. When I went to have my winter tires taken off today I noticed 2 of my older summer tires are all cracked in between the treads. So, I decided that I definitely need some new rubber at this point. So anyway, the information sticker on the center console lid of my Maxima states I need P215/55616 sized tires (I have the stock 1999 16 inch 5-spoke SE rims). When I looked at my summer tires, 2 are P215/55R16 and 2 are P205/55R16's. Is it okay for them to be different sizes? What is the difference between the P205/P215's?

I just bought the car in October and they gave me 2 new Yokohama AVID V4's (P205) for the front and the rear tires were older Goodyear Eagles (P215). I only drove with those for about a month then I got my winter tires - Nokian Hakkapeliita RSIs. For the winter tires they sold me P205's. I'm pretty sure I asked for 215's but can't remember exactly.

I don't know if this is a cause for concern or not. Can anybody help?