Shoot, this just occurred to me today.. what if the Dorman part is longer because it needs to be longer in order to stick out the same distance from my T170 hub and drum combination? I don't have it apart so I can't measure things up. At least it does look like the shoulder starts at the same place and the threads are just longer. Might not know for sure til I take it apart, or until someone else with a T170 axle buys a set of these wheels and does the stud update.

1965 C60 school bus | 1967 GMC 6500 school bus