The rims will hold 275/40/17, but I don't recomend them on the front as the tire actually points-out in the center because it wasn't designed for an 8 inch rim.
I have yet to see a manufacturer that recommends anything larger than a 255 for an 17x8 inch rim. The manufacturer's put charts with the recommended sizes on their websites, you can also go to www.tirerack.com and check them out.
I'd like to get a 255 width for the front. Ive got 275/40/17 in the back and 245/45/17 on the front. what size 255 in the front should I get to make it look ok? 255/45 oor 255/40?
I have 275/40/17s on 17X9 chrome Cobra Rs all the way around. The only time it ever rubs is full lock like in parking lots and if you don't listen for it you would never know. I'm also lowered 1.5 inches.
The Kumho's are pretty good i run 275/40/17's up front and i run a goodyear Eagle F1 GS-D3 315/35/17 in the rear and they are both good tires. I would say the goodyear have better grip in the straight but the kumho's have a harder sidewall. now if u really want cornerning performance I would go with a BFG G-force KDWS,or KDW.