Dr Diff Offest Kit With Oval Track Springs

I looked at mine this morning to confirm that it also was in a reverse arch condition. The thing I noticed is that the first leaf after the main leaf starts at about 8” or more from the eye of the main leaf. So, in effect, I think the reason it is S shaped is because the main leaf doesn’t have any support.

I think it is a bad design and would bet it doesn’t match the AFCO spring in how it is manufactured.

Interesting to me that it took 5/8” to relocated the axle centerline correctly. Makes it sound like the 1/2” long front segment might actually be within tolerance.