It depends on what axle you have. A 7.5 and 8.8 28 spline have a 2.75" O.D. axle tube while the 31 spline 8.8 has 3.25" O.D. axle tube
Originally Posted by TheRangerStation
My 94 Explorer Axle measures 3-1/4" O.D. . The U-Bolts are made from 7/16inch rod and are 3-3/8" inside x 7-1/2" long outside.
Size of stock ubolt depends on axle and if its 4x4 or not (has rear block or not). If your going to have u bolts made, just take them one of your old ones.