Since they are 15's, you can get a tire with a big sidewall. This means the sidewall will flex and you can accomidate a wider tire. If I were you I would decide on what brand/type of tire you want, look it up on the companys website (spec sheet PDF) and find the widest tire that fits your wheel width. You'd be supprised what widths you can get away with. Your wheel is 8 inches wide .. I think 275/60/15 DR will fit, so will 275/50/15 DR, and so will (yes its true) 295/65/15 DR's. Just remember to always keep the load rating and tire pressure in mind. Also 8" wide rear wheel factory specs are +16mm offset and 4.5" backspacing.
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