225 on stock 17"s with stock suspension should work.
Off road king has 225/75 on16" rims with a 1" lift kit. He had to trim the fender liner, 1/4 off the back of the from tire. The offset of his rims stick the tire out a little bit. I found that with 1" spacers on the stock trail hawk 17" wheels and 215 tires, it rubs the fender liner at full lock.
I just mounted 15" wheels with 235 tires with 1" spacers. Without spacers the 235 will probably rub the strut tub or spring perch. My setup rubs the front and rear of the front fender liner at full lock. I removed the fender liner and it still rubs on the back of the front fender at full lock.
Safer to stay with the original 215. Going up a size to 225 might require trimming behind the back of the front tire. 235 will probably need a lift kit, I'll find out soon if it has an effect.
Check out off road kings post and my post to see more info on the sizes we tried.