I'm thinking of purchasing the Toyo Open Country AT2's in 10 ply for my 2013 Sport. Will I have any issues running these with 3.55 gears vs the tires that came with the truck?
Are you sticking with the stock size or going bigger?
Either way you will lose a bit of power and fuel economy because of the increased weight of the tire. If you go with a larger size as well there will be a more significant drop of both. But I wouldn't let that stop you from doing that. I'm running 35x12.5 Toyo MT's on my 4.7 with 3.55's and it drives fine to me. Yes it takes a lot more fuel to get it going (especially up hills) but it's not near as bad as I thought it would be. I'm getting around 15.5-16 MPG with the tires so far. Which isn't bad at all.
Here's a link to my thread about the tire install and a bit of a review. You might find some of the information interesting.
They ride nice! Hooked up my GPS and the speed is the same. I'll have to see how the MPG is once I fill up next time. Now I just need to purchase a leveling kit.