Not trying to challenge your story, but measuring off the side wall just is not accurate enough. I'm surprised Snap On made such a thing. When we are talking a 1/16" desired result, the only way to get that precise measurement is going off a scribed line on the tire so you are getting a reading of what is actually on the road surface.
In the hundreds of old wheels I've checked, 1/16 runout is very good, 1//8 usable, 3/16 goes on the back, any more is a junk wheel. I've never seen a perfect wheel yet.
So, measuring off the side wall is not going to take into account that the wheel may not be perfect. Measuring front to back with a 2x4....ever seen a 12' 2x4 thats straight within a 1/6th?
My gadget I made with pipe and pointers is very accurate going off a scribed line from a spinning tire. However, its main purpose is so I can do it by myself with no help.
Its slow, many steps required. Best and fastest is 2 people and a tape measure, but I am usually only one people. Keep in mind, you are doing this all on jack stands, and if king pin bushings are bad it will change the results once its on the ground again
In the hundreds of old wheels I've checked, 1/16 runout is very good, 1//8 usable, 3/16 goes on the back, any more is a junk wheel. I've never seen a perfect wheel yet.
So, measuring off the side wall is not going to take into account that the wheel may not be perfect. Measuring front to back with a 2x4....ever seen a 12' 2x4 thats straight within a 1/6th?
My gadget I made with pipe and pointers is very accurate going off a scribed line from a spinning tire. However, its main purpose is so I can do it by myself with no help.
Its slow, many steps required. Best and fastest is 2 people and a tape measure, but I am usually only one people. Keep in mind, you are doing this all on jack stands, and if king pin bushings are bad it will change the results once its on the ground again