16,000 acre 1790 16/32 JD, Erratic spacing on main frame.

Rebuilt planter this past winter, started planting corn and noticed erratic spacing on the 6 main frame rows, wings were planting perfect, I move seed tubes and meters to different rows and problem stayed with mainframe. Rechecked all drive chains and drillshaft bearings, Long frustrating story short, finally replaced the "prodrive" cables and problem solved. Hope my loss of hair will help someone else. Dave

16,000 acre 1790 16/32 JD, Erratic spacing on main frame.