Is there an advantage to getting 121 load index tires on a 2012 GMC Crew Cab 4x4 pickup? As opposed to 113 or 115.?

Anonymous2015-10-28T20:24:44Z

113 rated tires are good to carry 2535 lb each.
121 rated tires are good for 3197 lb each.

How much are you expecting to carry?

Unless you make a living hauling bricks around, you aren't going to overload 113 tires, so there is no advantage to going with the higher rating. They will probably ride rougher because of the stiffer side walls.