ive got a 09 gmc sierra z71 with the stock 18 inch wheels... its about that time for tires and i was wondering what are the largest tires i can put under it. i have a 2 inch leveling kit installed. thanks for the help!

 

285/65/18 or 33x12.5

 

I second that, you might be able to go a bit bigger but I would look bad/rub and wouldn't be worth it