I need new tires for my 2009 V6 Mustang, and there are some Black Friday deals at Walmart, but none are an exact match for what I think I have on there now. So my question is, when buying new tires, do the numbers need to match exactly the same as the current tires? Specifically the 215 number. Can I have 205 or 220?
I would not buy tires from Wal-Mart, they usually don't carry top tier tires. Many of the tires they cary despite being name brand tires are only sold at Wal-Mart or Sams Club. This should tell you something. The Goodyear Tracker and Goodyear Viva tires are prime examples of this. Goodyear doesn't sell these tires in their own store nor do any other tire places sell these tires. Basically they are tires that Goodyear makes to Walmat specs (re: cheap as possible). I wouldn't trust such tires.
IMHO, there are two places that you absolutely *never* skimp on; tires and brakes. Do yourself a favor spend the extra money for some quality tires. Tirerack.com has good tires a decent prices. Costco does as well. And yes it would be best to stick the stock size of tire. In your case it should be P215/65/R16