They are both made by Gladiator. There may be some rubber compound difference but the same tire tread. I've been running a set of the Gladiator X-Comp ATR tires in 30/10R-14 size since before they came out to give them feedback on them. They are an awesome tire that is super tough. They ride smooth and climb everything I point them at.Just like the title says, is there a difference between the two? They both look like they are the same tire, just different sizes.