[joe_padavano]

Yes, your car has the GM midsize 5 x 4.75" bolt circle. Don't confuse rim diameter with tire diameter. The measurements that matter are TIRE outside diameter and width and WHEEL offset. For example, you can buy 20" (wheel size) tires with a smaller outside diameter than the 15" tires that came on your car originally (but PLEEZE don't do it - "rubber band" tires don't look good on these cars). Unless someone has prior experience and can recommend a particular tire size and rim offset, you probably are stuck with measuring. Every car magazine runs an annual wheel and tire issue and usually has the stock article about how to measure.