Its not so much what will fit the wheel as how big of a tire will fit in the wheel wells without "stuffing". Without the upcoming lift from Superlift, you really can't get any bigger of a tire than the stock. The largest possible tire size would be 275/60/17 but be careful. Some manufacturers only make certain tires in certain sizes. I would rather have an outstanding tire that is a little smaller than a mediocore tire thats just a little larger...thats my 2 cents
Hi Abmarsh. Welcome to the forum...another Michigander I see.
You're looking at a pretty old post, and Jangy hasn't been active since 2006.
What are you looking to do? Do you have a stock Commander? Are you wanting to put on larger tires without a lift? With a lift?
There are budget lifts in the 2 inch range available for the Commander for $200-$300 dollars as well as the more expensive super lifts. Also wheel spacers that put the wheel and tire more outboard for better clearance.
You can upsize from stock tires without a lift or spacers but not as much. So let us know what way you want to go.
If you do upgrade your tires I'd go with the Goodyear Wrangler Silent Armor's. Others on here have them and I'm planning on getting those when my Fortera's wear down. I've seen comments where they last up to 50k miles.