Your axles can only handle 35's maybe 37x12.5 pushin it
however . . .
I did used to run 10" of lift on my Z71 and ran 40x17 gumbo mudders on it, dang now now this thread's got me all wantin to put it on big tires again . . . .
Anybody think the IFS would hold up to 52" Michlins?
Yeah the axles under your burb (even though they are the 30 spline versions) with some decent wheeling would only be good to probably 37s, depending on the width and tread aggressiveness/ diffs being locked... but if you're just wanting to drive around and have 9" of lift, you could probably run 39.5s.
yeah you could prob clear 38-40" tires prob on the street, but id say under hte weight of a burb and v8 power, id be lucky to last much with anything over 35" if wheeled....