Spare tire size?

Can anyone tell me what size spare would have been on an 04 silverado 1500 w/ 17" wheels? Mine was recently stolen and the dealer is telling me that all the spares are 16" even though the truck came with 17" wheels and tires

Thanks

I bought an 04 brand new and it had 16's and the spare was the same as the others. I now have an 07 and they are 17's with the same size spare. Good luck.