How Big Can I Go????

I Have a 99 silverado ext cab. I was wondering what the biggest tires i could put on the truck with out lifting it was? Also would this give the truck the appearance of being lifted while saving me money? Or is it alot better to go ahead and lift it? Thanks for any help you can give.

U Did Not Give A Year I Have A 99 4x4 . 285"s Without A Lift Kit.315's With A 3" Body Lift After A Little Inner Fender Mods

i have fit 33x12.50s on my 99 4x4 ext cab SB