Coil steel traffic commenced before the CSX_ wagons could be placed into service.
Ten ELX_ wagons were modified to carry the coil steel. The class was altered to SLX. The numbers were 1 to 10. They were converted from ELX 43, 2, 46, 9, 44, 40, 31, 3 and 45 respectively. The conversions were done between December 1965 and March 1966.
The first CSX wagons entered service in Feb 1966.
Between May and August 1967, the SLX wagons converted back to ELX wagons with original numbers. By this time about twenty three CSX wagons were running.