No one is running 33's w/o a lift...that's 32's...not 33's.
And...as much as I like the 33's...I do wait to wear out what's on there...or sell them and use the money to defray the cost of the new rubber.
The tires are disposable, the bumper is durable...if you want the best ROI, go with the bumper, assuming you are eventually getting winch.
The 33's need room...and the shrock gives up-front room to flex the rubber/attack obstacles (Approach angle improvement)
33's will rub on compression w/o longer bumpstops (extensions) or a 2" BL...I like the 2" BL, as it preserves wheel travel.
I am running 33's now with a 3" SL + 2" BL...so I had almost no trimming to do.
My buddy with 32's and no lift had to remove the plastic parts, and hammer the metal ones.
The 31's will have mucho room to move in the meantime, when they are eventually replaced...you can get the 33's no problem.
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- TJ
2001 Xterra '03 VG33, SE 5 spd, 305/70/16's, Revolvers, UBSkidderz, Doubled AAL's, 3"SL/2"BL, winch/bumpers, skids, sliders, OBA, Snorkel, pine stripes....
Friends don't let friends drive stock.
http://www.gifsoup.com/view/501230/tj-tackling-crawlers-ridge-o.gif