Load wheel is 5 x 3.9 (YL-153) tandem Drive Tire is 13 1/2 x 5 1/2 x 8 Casteris 8 x 2 (HY-606)
Gave Jason at ITL-Memphis this infor for N30XMDR3 (and told him based on THIS model) per Jerry at VBS, the new versio they are bringing out now will take dual tandem RY-653HL (meaning they would need four wheels per fork)