Originally Posted by
NutDriver
Since 1/8" directly converts to 3.175mm, is there an effective difference between the two sizes (that's less than .007")? I've been told that there are, but I have a hard time believing that tolerances are tight enough, especially in a ball diff, for it to be a perceivable difference.
I have tried using 3mm balls (in lieu of 3.175mm) in the past and it all comes down to how thick the bearing is in the middle of the spur gear. If the bearing is thicker than the diff ball diameter, then the diff plates will not make solid contact with the diff balls and your diff will not work properly.