[the Suburbanite]

I think those are the rims that came on the 3/4 ton suburban back in that area

Pretty sure they stuck with the wheels OP posted from 19xx-2006 (or 2008) I think they changed the lug patterns on the trucks first, then the burbs a few years later. Pretty sure the "new" 3/4T wheels are not a direct fit for the older burbs, or that if they do fit, you have to use wobble lugs or something

 

[the Suburbanite]

The wheel in his picture is what comes on a 3/4 ton Surbaban from 08-13

Yah. They may have switched lug pattern on trucks earlier

 

[the Suburbanite]

Depends on the package once you get to 2007.5 - I think LTZ had 17" but the lower packages were still 16" if my mind is recalling correct. Could be LT and LTZ but I am not positive

The PYO's that the OP is talking about is from the "classic" style of truck (02-2007.5)

Your truck most likely came with a set of PYO's or steels on it and the previous owner found a set of take off P25's so he swapped them onto your truck.

Weirdly the half ton wheels still were the same lug pattern. (OT, but I digress)