285 is the widest you should gobecause any wider will cause the inner part of the tire to have most traction with the ground cousing most the rubber to be on the inside, also the lower the sidewall foe example "30" is bad because it is so close to the rim, that any bumbyou go over can harm the rim...i went with 275/35 19 on the rear with stock rims and that is the widest you should go for comfort...just cuz the tires are wider doesnt necessarily mean better performance