Biggest tire stock gmc

[jdoginc]

I found an awesome site. https://www.wheel-size.com/calc/?wheel1=255-70-16X7.0ET31

If I understand it correctly, there are many many sizes of tires I can put on my stock, extended cab, Sierra.  Seems to be too many.  Anyone know how big I can go, or how big have you gone?  I'd rather not lift, but if I do (1 inch, 1.5 inch maybe). I don't want it to look ridiculous with 255/70/16.  Lmk..need tires for winter.  Thanks!!  Also. 2wd.  

[CamGTP]

I believe a 265/75/16 would fit on those trucks. Search around and see if that size is what people run with stock 16's.