 After that there was a gap of long four years in the WDM3A production line in DLW.These new locomotives had their control stand shifted to the left side of the cabin.Meanwhile, Diesel Loco Modernisation Works (erstwhile Diesel Modification Works which again was known as Diesel Component Works) in Patiala started rebuilding the existing WDM2 locomotives, which had reached midlife, with upgraded powerpacks.