thanks for the input guys.
if i'm doing iroks, i'm goin radial, in which case i think tread life will be better than the bias version, without sacrificing much off-road.
for those saying the iroks won't last long, are you refering to the bias, or radials?
i had 34" ltb's when i first got the truck. i really liked them, but aside from the 40's, which i can't run, they don't have many big size options.
as far as the park's tire limit rules, they go by read size, I asked them saturday, as it is a major factor in my decision. the park, "the cliffs," says they enforce the rule to keep the trails from getting to torn up. they claim the bigger tires dig it up too much, and the park's owners are suzuki guys,

, so that kinda explains it.
there is lot of mud, at the park, and at the local trails, so from what you guys are saying, i'm thinking i need to stray from the iroks. however, the iroks are available in a 39.5 to fit my rims, so i'd save money, and i need a winch. I'd just hate to make a another tire decision i regret. I like my ssr's, but they are just wayy to small. at any rate, It's gotta be 39.5's