Goodyear doesn't make a Mud Terrain tire. Goodyear MT/R stands for Maximum Traction Radial not Mud Terrain Radial.

I've heard numerous people say that the MT/Rs aren't that great in mud, they are designed more for rock crawling.

-Michael

the MT/R stands for maximum traction reinforced... read the sidewall.

though, i do believe they are radials though...

david