You should easily be able to fit a 275/60R20 in there (32.99x10.83x20) The K2XX trucks have more room under the wheel wells than the NNBS for sure, and I think also the NBS trucks.

I don't know whether you want a tire that's wide, or tall....kind of a tradeoff in this case. I've seen guys fit a 275/65R20 (34.07x10.83x20), but that was on stock wheels which have around a +24 offset IIRC. So those wouldn't fit on a 9" wide wheel with a -12mm offset.

IMO, I think 275/60R20 would be the perfect fit for you.

EDIT: Just checked, the M/T doesn't come in that size, but there are other options on the market for sure...take a look at BFG KO2s, those are a great tire, as well as the Toyo Open Country A/T II.

 

IMO, I think 275/60R20 would be the perfect fit for you.

Awesome, thanks for your input n8dh! I don't mind wide or tall, kind of want the max on both without any rubbing.

I also realized that while I have my truck in my profile, I didn't include it in the post -- I have a 2014 Chevy Silverado Z71 (with the RC 2.5" leveling kit) in case anyone is wondering WTH I'm driving lol.

Thanks!

 

I saw a local guy with a 2015 Silverado running Toyo Open Country AT II's in 305/55/20 on stock wheels and a 2" level. I'm running the 295/55/20 Open Country A/T II's on 20x9 0 off sett my 2013 with a 4" lift. I think you need at least a 285.

 

Anyone else have any advice/insight into what size tires I should run? Thanks!