Re: The OFFICIAL 33\" tire on stock K5 thread Two sections, 15x10 and 15x8. 15x10 I have 33x12.50r15s on 15x10 Outlaw IIs with 4" of backspacing. I have the heavy duty front suspension (3 leaves and quad shocks) from the factory. The rear droops more than the front. I have the chrome trim. I cut it out where the tire was rubbing. I then proceeded to use a block of wood wrapped with a chamois and a hammer to beat in the lip so it didn't hang out. These were aftermarket fenders. When done, I took a pair of channel locks to the right fender at the leading end of the opening to bend the lip some more. The only place it will rub is the bottom edge of the fenders (where it curves under at the front and back). The only time it rubs is when I'm turning the right amount, braking hard, and hit a bump. It slops my suspension around and makes the tire kiss the fender. The gutter in front of my house makes it rub. I have yet to make it rub when offroading (but I bet if I had it turned and was going down a rock it'd rub) since most everything I see is stumps, rocker-ruining logs, and mudpits/berms/offcambers. I don't see many rocks. Oh, and I have found out that without a bumpstop (hey, it was in the way of my headers) my tire will touch the top of my wheel opening even with a sway bar. 15x8 As long as you don't have droopy springs and sloppy bushings they'll fit. My uncle and some of my Dad's friends used to off-road back in the 80s. I have seen pictures of these trucks (and one K5) with 33s on them flexed out. My parents' neighbors friend used to tear his truck apart so often I joked that he should put it together with wing nuts. He ran beadlocks which I didn't understand until I got into ATVing. Anyway, he had a single wheel 1 ton with 33s for the weekend and some kind of skinny tire turning the week (hauled construction trailer). He was hardcore into it, he pulled both sway bars each weekend and put them on Sunday night. Moral of the story: 33s on 8" wide wheels with 4" of backspacing will fit as long as you don't have droopy springs or an axle that isn't centered in the hole. Sloppy bushings are a bad omen as well. What does this mean? <font color="red">Since these trucks have been out of production for more than ten years it's a case by case situation as to whether 33s with any rim combination will fit or not due to all the spring sagging, body sagging/shifting, and axle wandering that can happen in this amount of time.</font color> My experience: 31x10.50s on 15x8s (4" bs) fit with a fist's worth of room. 33x12.50s on 15x8s (4" bs) fit with about 1.25" of room. 33x12.50s on 15x10s (4" bs) fit with about .5" of room. I did my testing on my truck with the truck in gear with the brakes on (neighbors are good for something) with the tires turned to the spot where it was closest. On my truck, the closest spot is on the driver's side at the bottom of the fender towards the cab.