BklynJay

iTrader: (3)

Can they fit the GS properly or not is the first question? Second is what is the widest tires i can put on these? 245/40/18 Front and 255/40/18 Rears is the rim width to skinny?

rominl

iTrader: (4)

yes it will fit,but i will add it very conservative

you can put 245, but i think that's a bit wide already, i would do 235. 255 imho is too wide

BklynJay

iTrader: (3)

So put 235 in the front and 255 in the back you say'in or just 245 all around?

rominl

iTrader: (4)

since you have the same width, i'd just do the same tire 235 all around

Mrbig

245/40/18 Should work fine !!!

Neo

iTrader: (3)

235/40 (optimal) or 245/40 should be fine. I would NOT do 255. It may mount but I would not feel safe. I would stay with one size, though. If you were going to stagger the tires, it would have been better to stagger the rims appropriately to maintain a consistent wheel diameter.