Friend of mine is running 37x 13.50 R 18 Nitto Mud Grapplers on a Poison Spyder 18 x9 rim. They do rub pretty well on his front fenders, front wheel wells, and front bumper, and on the rear fenders. He is not using any wheel spacers and has a Skyjacker 4" lift. On the good side, those tires have excellent sidewall "bite" and perform very well on rocks, in soft mud, and on steep hill climbs. I don't know what load range they are, however, I am running 35 x 12.50 KM2's on 17s and they are "D" rated. They handle excellently on the road and are very quiet compared to the Swamper SSR radials (that I had on a TJ).
*He used very little weight to get them to balance although others say that they DO take a lot to get them balanced correctly. They seem like they would require a lot of weight to get them right.
*He used very little weight to get them to balance although others say that they DO take a lot to get them balanced correctly. They seem like they would require a lot of weight to get them right.