Did anybody buy an XTS that has a spare. So long story short I didn't, they don't offer the kit, I had to piece it together, and am going to fabricate it myself. I have the rim, its an 18. But I don't know the tire size. If you have an XTS can you see what tire size you have? It should be on the driver side door jam a sticker that shows front back and spare, it should say the exact size tire that goes on your spare, if not it will say it on the tire itself. I found the GM part for the tire however i'd rather get it off tire rack its much cheaper. Thanks! Cheers!